The biblical axiom—God's Word as the starting point of all truth

Book text · 4th, corrected edition 2026

Goal: Justifying why God's Word is the only sound starting point

If everyone needs an axiom in thinking—a fundamental assumption not further justified—the decisive question inevitably arises: Which axiom holds? Which foundation does more than sustain a subjectively good feeling, offering a robust foundation for objective truth? Which criterion is strong enough to support the whole building of knowledge, morality and meaningfulness?

The Bible gives a clear, uncompromising answer: God's own Word is the source of all truth. It is not simply one of many voices in the chorus of human opinions. It is the criterion against which all voices must be measured. It is no pious suggestion but the ultimate starting point itself. This starting point is no abstract principle but a person. The Logos. And this person has spoken.

This chapter therefore develops two central statements:

1. The Bible is binding not merely for Christians but epistemologically necessary for all people.

2. Only God's self-revelation in Holy Scripture supplies an axiom simultaneously absolute, consistent and viable.

We begin with what the Bible says about itself. We then show why no other foundation suffices—whether reason, science or religious feeling. Only God's Word can be the beginning of all knowledge, and everything else ultimately ends in contradiction or arbitrariness.

2.1 The Bible as criterion and beginning of all knowledge

2.1.1 Not human words, but God's revelation

The Bible understands itself not as a book of religious ideas merely collecting human thoughts, experiences or pious insights. It makes a far greater claim: It is revelation. This means it is no human attempt to reach God; rather, God himself has bent down to us and spoken.

It is not the product of religious intuition or spiritual searching but God's own Word. It therefore also stands above everything else humans have ever written, felt or thought, not merely in content but fundamentally. It is from above. It is inspired, not merely inspiring. It is God's communication about himself and not merely a report of our experiences with him.

“All scripture is breathed out by God...” (2. Timothy 3,16)

“For prophecy was never brought forth by human will, but holy men of God spoke, driven by the Holy Spirit.” (2. Peter 1,21)

Anyone grasping this realizes: The Bible is not simply one of many perspectives on truth but the truth judging all other perspectives. It is not a criterion; it is the criterion.

If someone says “I believe only what I can examine,” they have therefore already decided that their own thinking stands above the Bible. But if the Bible truly is God's Word—as it claims—it is not the object of our examination but the criterion according to which we should examine everything.

The Bible is no accused person in the dock of human reason. It is the judge. It judges us, not we it (cf. Heb 4,12). The question “How can you be certain the Bible is true?” is therefore not simply a neutral epistemic question but fundamentally: “Can God be trusted?” Anyone doubting this places themselves above the Creator.

“Oh, your perversity! Shall the potter be regarded as equal to the clay? Shall the work say of its maker: He did not make me! And the formed thing say of its former: He does not understand!” (Isaiah 29,16)

The Bible carries within itself everything necessary to be recognized as God's Word. It cannot be assessed “neutrally,” for it itself is the foundation on which every assessment becomes possible. Without the Bible we have no sound foundation for truth, reason or knowledge. It therefore need not first be proved. It is what everything else rests on, and proofs are inconceivable without it.

Anyone believing it submits to God's authority. Anyone rejecting it places another authority in its stead—usually themselves.

The decisive question is therefore not “Do I feel comfortable with what the Bible says?” but “Is the Creator speaking here?”

2.1.2 How the Bible speaks about itself—authority, truth, inspiration

The Bible is no reserved book. It does not proceed cautiously or make suggestions one could accept or reject. It speaks with a claim. It sees itself not as a contribution to an open religious exchange of opinions but as God's authoritative Word. And it makes clear itself how it wants to be understood: as authoritative, true words breathed out by God himself.

“Sanctify them through the truth: your Word is truth.” (John 17,17)

“Thus says YHWH.”—over 400 times in the Old Testament

“If anyone thinks himself a prophet or spiritual, let him recognize that what I write to you is a commandment of the Lord.” (1. Corinthians 14,37)

Scripture claims divine authority because its author is God himself. It not merely says true things about God; it is God's speaking. It therefore describes itself as inerrant (cf. Ps 19,8-10), imperishable (Mt 24,35), perfect (Ps 119,160) and—as Revelation exemplarily emphasizes—not to be supplemented (Rev 22,18-19; cf. Deut 4,2; 12,32). Its authority is not derived from outside, not from church, tradition or human reason. It stands on its own feet. The Reformers called this its autopiston character: The Bible is credible in itself.²⁴

This means: The Bible is not merely a good argument for God but the starting point of all argument. It seeks no confirmation through our reason but is the criterion against which all reason must be measured.

Van Til holds that the Bible is not simply one possible argument among many for God's existence but forms the fundamental starting point for any argument at all. He criticizes the widespread idea that from an allegedly “neutral” standpoint one could collect arguments, examine indications and only afterward decide whether the Bible is reliable. For Van Til this is a wrong path: Anyone thinking this way already installs human reason, experience or tradition as ultimate authority and subjects God's Word to human judgment. Christianity must instead be accepted and presupposed in its entirety as the system of truth before its individual parts can even be rightly understood.²⁵

Van Til thereby emphasizes the principle of scripture's self-attestation. For him, the Bible is more than a human report about Christ; rather, it is Christ's own testimony about himself.²⁶ Its authority therefore cannot first be authenticated through philosophical presuppositions or ecclesiastical decisions. Anyone attempting “first” to justify the Bible through human criteria and then learn of the Bible's God on this basis has already surrendered the foundation.

Van Til emphasizes instead: The Bible is the inspired, infallible Word of God, subject to no human tribunal's judgment.²⁷ It is no light floating along in the stream of other arguments but the light in which all other facts and experiences can be interpreted at all. This means: All natural data, historical events, moral convictions and logical principles gain their meaning only when understood from the biblical revelatory standpoint. Van Til therefore insists that scripture is the divine light in which the whole cosmos, all thought and all experience must be interpreted—because it is God's infallibly inspired revelation to sinful humanity.²⁸

One can also say: The Bible is no book about God but God's speaking itself. Anyone attempting to stand above this speaking has already crossed the boundary. The Bible does not demand that one bend critically over it. It places us under its judgment:

“For God's Word is living and effective and sharper than any two-edged sword, penetrating to the division of soul and spirit, both joints and marrow, and judging the heart's thoughts and intentions; and no creature is invisible before him, but everything lies naked and exposed before the eyes of the one with whom we have to do.” (Hebrews 4,12-13)

In our time one is quickly tempted to treat the Bible as an ancient religious document: analyzing, comparing and criticizing as though it were one cultural artifact among many. But the Bible cannot be taken apart like an object in a laboratory. It is no object of investigation—it is the speaking subject. It explains, defines and judges. And it does this not on request but with authority.

The Bible does not ask to be believed—it demands faith. It does not apply in the “marketplace of worldviews” to perhaps be accepted as an option. It speaks with God's voice, not human uncertainty. Anyone contradicting it rejects not merely a thought but the living God.

The actual problem is not the Bible's incomprehensibility but humanity's unwillingness to submit to its authority. The Bible is therefore the clearest book and simultaneously the most misunderstood. The reason lies not in the text but in the reader's heart. The decisive question is therefore not “How can I prove that the Bible is God's Word?” but “Do you recognize your Creator's voice when you hear it?”

2.1.3 Self-attestation or circular reasoning?—why the Bible attests itself

A frequent objection to our approach is: “You say the Bible is God's Word because it claims so itself. That's circular! That's no proof!” But this objection overlooks something fundamental: Every absolute authority must ground itself. If it had to rely on something else, that “other” would be the actual authority rather than itself.

This applies to every worldview: An axiom always stands at the beginning, a starting point that cannot first be proved through something else, because otherwise one would never arrive anywhere. Wanting to justify everything would require justifying the justification and its justification too... endlessly onward.²⁹ Such thinking ends in nothingness. Every system of thought therefore needs a starting point that holds “from itself.” The decisive question is thus not “Is this circular?” but “Is this circle true, coherent and sound?” For not every circle is false. Only a circle contradicting itself is impermissible. But an axiom confirming itself without generating internal contradictions is precisely what every worldview needs and only the Bible truly offers.

It is therefore no deficiency that the Bible attests itself as God's Word. Quite the opposite: Precisely this shows it to be the necessary and sufficient prerequisite of highest authority. For if it had to appeal to something else—reason, science, church or experience—it would be subordinate to them. Humanity would then be the criterion, no longer God. But God's Word is no petitioner in human reason's courtroom. It is the judge. It can only attest itself because nothing stands above it.

“The law of YHWH is perfect, refreshing the soul; the testimony of YHWH is reliable, making the simple wise. The precepts of YHWH are right, rejoicing the heart; the commandment of YHWH is pure, enlightening the eyes.” (Psalm 19,8-9)

If someone says “I believe the Bible only if human logic or research can prove it,” they have thereby already decided that humanity stands above everything, not God. This is no neutral skepticism but usurpation of the throne.

Scripture's self-attestation is therefore not circular in an irrational sense but the only possible and consistent starting point. And precisely this makes it so distinctive: Only the Bible can raise this claim without contradicting itself.

Ultimately every person has only two options:

➞ Either they begin with a created criterion (such as the mind, senses or consensus) and end in contradiction or arbitrariness.

➞ Or they begin with God's revealed criterion and recognize: Only the Bible can rightly stand at the beginning.

2.1.4 Only the Bible explains why anything makes sense at all

The question of a reliable starting point is no abstract game for philosophers. It is entirely practical and concerns everyone. For we all think, speak, assess and make decisions. But on what basis? What do we actually rely on?

Everyone lives from certain fundamental convictions. These convictions shape how we see the world and thus what we consider logical, right or important. Without such convictions, we could not even conduct a conversation. But the decisive question is: Can these convictions truly sustain us? Are they stable or merely felt to be true?

When seeking a reliable foundation, the ultimate question is:

• What must first be true for anything to make sense at all?
• What must exist for us to speak meaningfully about logic, morality, truth, history or identity?

The Bible gives a clear answer to this question, and it is unique in its clarity:

• Only if God reveals himself does the world become intelligible.
• Only if God speaks is there an order one can rely on.
• For God is the world's Creator, the world's sustainer and history's goal.

The Bible does not merely show us what is right. It explains why anything can be right or wrong, true or false, meaningful or meaningless at all.

This is the deeper approach of axiomatic apologetics. It asks not merely “Is Christianity logical and reasonable?” but more deeply: “What must exist at all for logic and reason to be possible?” For Christianity is not simply one worldview among many. It is the foundation on which worldview becomes possible at all:

• Without God one may still make words, but no meaning.
• Without revelation one can talk a great deal but know nothing with ultimate certainty.
• Without a firm foundation everything remains relative: morality, truth, even thinking.

The Bible begins a worldview that not only explains but makes everything explicable at all. A foundation supporting not merely when things are easy but also when they become hard. A light not merely shining itself but through which we recognize everything else at all.

Without God's revelation, the ground beneath our feet is missing

If someone rejects God's self-revelation—as we encounter it in the Bible—they lose far more than a religious opinion. They lose the ground on which anything can be reliably thought, said or known at all. For imagine what it would mean if there were no personal, eternal God who created this world through his powerful Word (cf. Heb 1,2-3.10-12; 11,3; Jn 1,1-3).

If there were no criterion outside this world showing what is good and true. If no reliable order watched over the world (cf. Col 1,17). And if humanity were not created in God's image, thus incapable of understanding, thinking, speaking and loving (cf. Gen 1,27). What would remain then?

• Then our thinking would be merely a chance product of biochemistry. Our thoughts would be like waves on a lake—visible, yes, but meaningless.
• Then “logic” would be nothing but a pattern in our brain's synapses.
• Then “truth” would be an evolutionarily useful deception, an illusion helping us survive but not know.
• Then “meaning” would be something we must invent because none exists.
• Then humanity would be not God's image but a collection of atoms without goal, purpose or meaning.

In such a worldview—where there is no Creator who speaks—there is also no possibility of justifying why we believe in natural laws, morality, identity or responsibility. Everything becomes relative. Everything becomes questionable. “Knowledge” is then merely subjective feeling, “good and evil” merely matters of taste, and “I” merely a random thought in the head. What remains is time's rushing noise. A river without source, goal or interpretation.

Anyone rejecting God's revelation may ultimately still believe in words but has no reason left why these words should mean anything true.

Only the Bible supplies the presuppositions for meaning

The Bible does not merely give good answers to important questions. Far more fundamentally, it explains why answers are possible at all. For certain things must be presupposed for our thinking, speaking and living to make sense at all. And only the Bible supplies precisely these presuppositions:

1. Logic is possible because God himself as the Logos is the eternal, rational Word (Jn 1,1).

➞ Thinking is no chance product but an image of divine reason.

2. Order in the world is possible because God sustains and holds everything together through his Word (Heb 1,3).

➞ Natural laws are not merely observed patterns but expressions of divine faithfulness.

3. Morality is possible because God's being is good and he has written a law in our hearts (Rom 1,32; 2,15).

➞ Just and unjust are no opinions; rather, they originate in God's character.

4. Knowledge is possible because humanity is created as God's image (Gen 1,27) and can recognize real truth (Jn 17,17; Prov 1,7).

➞ We are not merely clever animals; we are created to know God.

5. History has meaning because God is Lord of time and directs everything toward a goal (Isaiah 46,9-10; Acts 17,26-27).

➞ History is no cycle or chance—it has a divine direction.

These five points—logic, order, morality, knowledge and history—form the basic framework of every interpretation of the world. But only the Bible offers an explanation truly grounding these things. All other worldviews live from them but cannot justify them.

What does this mean?

➞ Having good thoughts is insufficient. One must also be able to show where they come from and why they are reliable.

➞ Every worldview claiming to make sense must be measured against these five points. And only the biblical worldview holds at every one of them.

Comparing worldviews: Borrowings and contradictions

Many people reject the Bible but nevertheless live intellectually from things making sense at all only within a biblical worldview. One could say: They borrow biblical presuppositions without noticing and without returning them. But this is dishonest and unsound. For one should also be able to justify what one uses.

Some examples:

• The atheist says: “I believe only what I can see and measure.” Yet they simultaneously speak of logic, truth, morality, human dignity. But where do these things come from if only matter and energy exist? ➞ Matter does not think. Chemical processes know no logic or morality. What remains is a worldview without a source of truth but constantly using it. A contradiction.
• The Muslim says: “Allah is entirely different: untouchable, indivisible, transcendent.” Yet they simultaneously say Allah has revealed in human language what humanity should know. ➞ Either this revelation is literally intelligible, in which case Allah is not truly transcendent, ➞ or it is merely symbolic and analogical, in which case humanity can know nothing certain. In both cases an epistemological dilemma arises that cannot be resolved (cf. 3.1.5).
• The relativist says: “Truth is subjective. There is no absolute truth.” Yet they then assert precisely this sentence as valid for everyone. ➞ They expect agreement, thus recognition of an objective truth. But they thereby contradict themselves. They use truth to deny truth (cf. 3.1.4).

All these worldviews borrow basic structures such as logic, morality, meaning or language but cannot explain where these things come from or why they should hold. Only the Bible is internally coherent. It asserts nothing it does not also ground, and supplies what it promises. It is the only worldview not merely using but also explaining the presuppositions of knowledge, morality, meaning and truth.

The light through which we see everything else

C. S. Lewis wrote:

“I believe in Christianity as I believe that the sun has risen—not only because I see it, but because through it I see everything else.”³⁰

This image captures what the biblical axiom is:

• Not one light source among many, but light itself.
• Not merely an explanation, but the criterion through which everything becomes explicable.

The Bible is not merely an intelligible book; rather, it makes understanding possible at all. It does not merely give meaning but is the prerequisite for anything to make sense at all. For without God's light, we may see shapes, shadows and movements—as in darkness. But we recognize nothing truly. God's Word does not merely illuminate—it opens reality. Psalm 36,10 therefore also attests:

“For with you is the fountain of life; in your light we see light.”

Knowledge is not first an achievement of the intellect but a gift of the Creator.³¹ Anyone shutting themselves off from God's light remains—like someone with closed eyes—surrounded by truth but blind to it.

The Bible is not merely true—it is the prerequisite for truth

Anyone rejecting the biblical axiom does more than discard an opinion. They sever the foundation on which knowledge, truth and meaning rest at all. They pull the ground from beneath their own feet and then stand in emptiness. But anyone beginning with God's Word places their thoughts, questions and entire life on the One who sustains everything, preserves everything and fills everything (cf. Heb 1,3; Col 1,17).

The Bible is therefore no option among many. It is the starting point without which no sound path exists. Not because we could prove it with something else but because without it nothing exists that would be provable at all.

The Bible is not merely true. It is the prerequisite for our even being able to grasp what truth is.

Summary of section 2.1

2.1.1 The Bible—not human words, but God's revelation The Bible understands itself not as a book of religious thoughts but as God's direct revelation. It is no human search for God but God's speaking to humanity. Its authority is not derived—it rests on its divine origin. The Bible is therefore no opinion among many but the measure of all things. Anyone wanting to examine it places themselves above it—but if it truly is God's Word, it must not be treated as a thesis but is itself the criterion of every examination. The Bible is not interpretable but interpreting truth—it is the criterion, not the object of investigation.

2.1.2 Authority, truth, inspiration: How scripture defines itself The Bible speaks with divine authority because its author is God. It is not merely true—it is truth (cf. Jn 17,17). It claims inerrancy, completeness and eternal validity. Its authority does not depend on confirmation through reason, tradition or science. Rather, it is credible in itself (autopiston): It is the touchstone, not the examinee. Anyone thinking it must first be confirmed has not understood its claim. The Bible speaks not on equal terms—it speaks as judge. It demands faith, not conditional agreement.

2.1.3 Self-authentication versus circular justification A frequent objection is: “You believe the Bible is God's Word because it says so itself—that's circular!” But this misunderstands every axiom's character: A first principle cannot be proved through another—otherwise that would be the actual axiom. The circle is therefore not the problem—the question is: Which circle holds? The Bible justifies itself because there is nothing higher on which it could rely. Its self-authentication is no logical error but an expression of its highest authority. Anyone rejecting it thereby places humanity above God, and this is not doubt but rebellion.

2.1.4 Only the Bible explains why anything makes sense at all The question of the axiom is not merely philosophical—it is existential: What must be true for thought, language, logic, morality and history to be possible at all? The Bible's answer: Only if God speaks can humanity understand. Only the biblical worldview supplies the presuppositions for meaning. The atheist uses concepts such as logic and morality—but cannot ground them in their worldview.

The Muslim speaks of revelation—but cannot ground it as reliable within their theology. The relativist denies truth, but only by presupposing truth. Only the Bible supports what it asserts. It is not merely meaningful—it makes meaning possible at all.

Reflection questions for section 2.1

2.1.1—Not human words, but God's revelation

• What concrete differences do you see between a human word about God and God's own Word to us?
• Why can the Bible—if it truly is revelation—not be judged neutrally like another book?
• When have you experienced temptation to judge the Bible rather than letting it judge you (cf. Heb 4,12)?
• What does it mean for your everyday life that the Bible need not first be proved but is itself the foundation of truth and knowledge?

2.1.2—How the Bible speaks about itself—authority, truth, inspiration

• How would your Bible reading change if each time you consciously assumed that God himself is speaking to you now?
• Which biblical verses or statements show you particularly clearly that it does not ask for agreement but speaks with divine authority?
• Why is scripture's “autopiston” character (self-attestation) no weakness but a necessary consequence of its claim?
• How do you deal in conversation with people seeing the Bible merely as one religious opinion among many?

2.1.3—Self-attestation or circular reasoning?—why the Bible attests itself

• Why must every ultimate authority attest itself, and why would it be contradictory if it did not?
• How would you explain to a skeptic why the accusation of “circular reasoning” misses its mark in the Bible's case?
• In which situations do you experience people elevating their own reason as criterion above the Bible—often without noticing?
• What especially encourages you about “The testimony of the LORD is reliable” (Ps 19,8)?

2.1.4—Only the Bible explains why anything makes sense at all

• Why is having good thoughts or moral values insufficient if one cannot also explain their foundation?
• Which of these five presuppositions (logic, order, morality, knowledge, history) has most clearly shown you personally that only the Bible holds?
• Where in conversations have you experienced your counterpart using biblical presuppositions of thought but being unable to justify them?
• What does it mean that the Bible gives not merely meaningful answers but is the prerequisite for meaning to be recognized at all?

2.2 Why God's Word is the only firm starting point

If all knowledge needs a foundation, everything stands or falls with which starting point truly holds. The Bible claims not merely to speak truth but to be the beginning of truth itself. It is not merely content but criterion. Not merely communication but origin.

In the following sections we develop why only God's Word can be a sound axiom and how it logically and spiritually excludes all other options.

2.2.1 Scripture as the norm of all norms: The Bible is the axiom

If the Bible truly is God's revelation, it is no voice among many but the highest authority from which everything is judged. It is no contribution to seeking truth but truth itself, examining, correcting or rejecting all other voices. It is not merely true but the criterion of truth.

“The Bible is the axiom” therefore means:

• It is the starting point, not the result.
• It is not measured; rather, it measures everything else.
• It is not dependent on reason, history, empirical inquiry or feeling but the origin of all categories of assessment.

Anyone wanting first to “verify” it before believing it places themselves above it and thus above God himself. But God's Word is no argument seeking to persuade; it is a voice speaking with authority. It does not explain itself in the light of human criteria but is the light in which everything else must be known (cf. Ps 36,10; Jn 1,9). Anyone attempting to measure it against another criterion—speculation, intuition, logic, history, feeling—has thereby already denied its authority.

Therefore, not “What does science say?”, not “What feels coherent?”, not “What is logically comprehensible?” but: “What does scripture say?” This is the highest norm.

Anyone thinking scripture must first be confirmed through science, archaeology or logic has thereby already shifted the criterion away from God toward humanity. For they declare: “God's Word holds only if it agrees with our methods.” But the creature thereby elevates itself as judge over the Creator.

If God is the source of all truth, however, it necessarily follows that his Word is the measure of all things. We do not judge it; rather, it judges us. We do not legitimate it through external proofs; rather, it is itself the touchstone against which everything else must prove itself. Anyone asserting otherwise has already forgotten who God is and who humanity is.

This insight has consequences:

• For theology: Only statements agreeing with scripture are theologically valid.
• For apologetics: Only arguments proceeding from scripture have ultimate authority.
• For knowledge: Only knowledge anchored in God's revealed Word is truly certain.

If the Bible is not our ultimate authority, something else is. And whatever this “something” is—reason, science or experience—it thereby becomes our god. For what we ultimately listen to, what we give priority to when in doubt, is in truth our criterion. Anyone placing something else above God's Word has already replaced it not merely methodologically but spiritually.

Acknowledging the Bible as the axiom—the highest starting point—is no mere methodological decision but a spiritual commitment. For if it truly is God's Word, it is also the highest authority. It is the criterion against which all other criteria are examined, but it itself is examined by nothing else. Theology calls this: norma normans non normata. This means: “the norming norm that is not itself normed.” In other words: The Bible sets the tone, not vice versa.

Anyone acknowledging this stands firm, having built on divine revelation's rock (cf. Mt 7,24). But anyone relativizing this criterion or replacing it with other sources—human reason, tradition or experience—loses not merely the biblical foundation but also the firm ground beneath their feet. They are left with a worldview that cannot be defended rationally, morally or spiritually. For only God's Word bears the claim and capacity to judge everything without itself being judged (cf. Heb 4,12).

2.2.2 The argument from indestructible consistency (coherence)

A key element in axiomatic argument is coherence, not in the sense of mere logical order but as an expression of divine truth itself. The Bible is true not merely because revealed but because it forms an internally perfectly coherent system explaining itself and capable of judging every other system.

Consistency (coherence) means that all scriptural statements fit together—like parts of a well-built house showing neither shakiness nor cracks. The point is not merely that individual verses taken separately are true but that the whole yields a coherent, consistent picture: of God, the world, humanity and life's meaning. Everything fits together. No other vision of the world offers such internal agreement in doctrine, history, morality and meaning. This shows: The Bible is not simply a collection of religious statements but a fully thought-through whole revealed by God.

The Bible is not merely internally logically coherent—it is the only system able to claim universal and absolute coherence. Why? Because it originates not in human limitation but in God's Spirit himself, and God is truth (Jn 14,6).

What God speaks does not contradict itself. His revelation forms no miscellany of religious opinions but a thoroughly coherent whole—from first verse to last. Only the Bible can claim truly to explain the world in its depth because it originates with the one who created it. Its coherence is no accident; it is the seal of divine authorship.

What does “indestructible consistency” mean?

• Scripture contradicts itself in no area: neither theologically, logically nor ethically. Its unity expresses God's unity.
• It sustains itself and need not be supported or supplemented by external systems.
• It orders reality, not merely the spiritual sphere but thought, morality, history, language, science and society.
• It exposes the contradictions of all other worldviews while itself remaining steadfast.

The Bible is no house of cards collapsing at the first gust. It is a rock, unshakable even when the whole world assaults it. Anyone examining it discovers not weak points but an inner power withstanding every honest doubt. Anyone attacking it soon discovers that in doing so they must employ concepts and principles making sense at all only in its light. For it does not merely explain truth but makes truth possible. All systems fighting it ultimately stand on the ground they deny and fall through their own illogic.

Here the difference from secular or syncretistic worldviews becomes visible: At first glance they may seem coherent in some areas, but at the level of basic assumptions they collapse. They can neither explain nor support nor secure their own foundations. God's Word, by contrast, is no shaky edifice of thought that must bow to human criticism. It is living and powerful like a sword (Heb 4,12): It not merely answers questions but also searches the questioners. The Bible does not sit in the dock; instead, it remains the judge. Anyone thinking they can refute it uses intellectual tools that would have no foundation without it at all. Every attack thus ultimately exposes not scripture's weakness but humanity's weakness without it.

All false worldviews carry the seed of their own collapse within themselves. Sooner or later they stumble over their internal contradictions and collapse. The Bible, by contrast, endures. Its truth is not the result of human cleverness or chance but an expression of divine perfection. It does not contradict itself because it originates in the one who cannot lie (Tit 1,2), whose thinking is perfectly coherent. Its unity can be explained only thus: Its author is God himself.

The Bible's internal consistency is therefore no mere logical argument but an indication of its divine origin. Scripture is coherent because it originates in a single, perfect, omniscient mind—not a patchwork of human traditions.

The conclusion is clear: Anyone wanting real coherence needs an ultimate authority. Anyone seeking an authority must be willing to listen. And anyone listening will recognize: “Your Word is truth.” (Jn 17,17)

2.2.3 The principle of sola Scriptura within apologetics

The Reformation confessed with complete clarity: Scripture alone is the highest and ultimate authority for faith and life. This principle—sola Scriptura—is no historical slogan but a radical act of submission to God's self-revelation. It is indispensable especially in apologetics.

Many think one must agree on a “shared foundation” with the unbeliever, such as reason, experience or nature. But anyone proceeding this way betrays sola Scriptura at its most sensitive point: They methodologically posit another norm alongside or even above scripture.

If we believe the Bible is God's Word, we must not treat it as an explanatory attempt needing examination and first requiring confirmation through human logic or research. It is not the result of our arguments but their starting point. Apologetics therefore means: We defend faith from scripture, not without it. Anyone wanting first to examine God's Word before trusting it elevates humanity above God, and this is the actual error.

The Bible's authority is indivisible. Either it is God's Word, and then it is the norm for everything, including our reflection on it. Or it is not, and then it remains one human opinion among many. No middle way exists.

Every apologetic method not grounded in sola (“alone”) and tota Scriptura (“the whole scripture”) is therefore problematic. Anyone wanting to prove the Bible “from outside” makes it dependent on something else (logic, science, history) and thereby elevates precisely this “other” into the actual authority. True apologetics begins not outside but with scripture. We argue not from below upward but from God's Word, which inherently carries divine authority.

The axiomatic approach is uncompromisingly biblical here: It defends scripture with scripture, not from irrationality but because only the highest authority can justify itself. Everything else would be methodological self-deception.

Sola Scriptura in apologetics means:

• no neutral criteria above the Bible
• no methodological subordination of revelation
• no arguing “from outside,” but from scripture's authority

For “God's Word is living and effective and sharper than any two-edged sword” (Heb 4,12). We need no alien weapon to defend it—we need only draw it.

2.2.4 Consequences for knowledge, morality and understanding the world

If God's Word is our axiom—the first principle, highest norm, foundation of all truth—this has far-reaching consequences. The Bible is not merely a pious book for religious people. It is like glasses through which we must see everything else: thought, life, history, science, morality, identity, language—nothing remains neutral, nothing untouched.

1. Knowledge: Scripture as the foundation of understanding

Only the Bible gives a reliable basis for knowledge. Without God's revelation, humanity remains trapped in uncertainty and contradiction. True knowledge becomes possible in God's Word because it comes from the omniscient Creator's mouth (Prov 2,6).

“[Christ,] in whom all the treasures of wisdom and knowledge are hidden.” (Colossians 2,3)

2. Morality: Scripture as the criterion of good and evil

The Bible alone reveals what is truly right and wrong, not relatively, not dependent on culture but in the light of God's being. Morality is no human agreement but an expression of God's holiness. Anyone separating it from God's revelation loses every binding force.

“Your Word is a lamp to my feet and a light for my path.” (Ps 119,105)

3. Understanding the world: Scripture as the key to reality

The Bible is not out of touch with the world but opens it up. It explains creation's origin, meaning, goal and condition. Without it, the great questions remain unanswered: Where do we come from? Why are we here? Where is everything going?

“According to your ordinances they stand today, for all things serve you.” (Ps 119,91)

Anyone not accepting the Bible as fundamental criterion loses not merely the Gospel's saving truth but also the ability to interpret the world rightly. Everything in nature, history, morality and thought points to God (cf. Rom 1,19-20). But without scripture's light, humanity remains blind to these indications' meaning. People live amid a world full of God's traces yet do not truly understand them.

The biblical axiom is therefore no mere theological assertion but the basic condition of meaning itself. Anyone rejecting it loses access to reality. Anyone confessing it finds truth, clarity and life.

“Sanctify them through the truth: your Word is truth.” (Jn 17,17)

2.2.5 Why Christianity rather than another religion's God?

So far we have seen: The Bible is not one of many possible sources of revelation. It is the only one sustaining itself, supplying knowledge's presuppositions and thereby logically excluding all countermodels. But how can this be made methodologically clear?

The theologian Vincent Cheung³² gives a clear answer in the section Excluded by Necessity (“Excluded through necessity”). He says: We need not laboriously refute every individual alternative worldview. Instead we should begin deeper and ask: What must hold at all for truth to exist?

Cheung's argument is simple and sharp: Truth automatically excludes everything false. Just as “1 + 1 = 2” excludes infinitely many false results, the biblical worldview likewise excludes all non-Christian worldviews from the outset—by logical necessity. What is decisive is therefore not refuting every individual alternative but positively presenting Christian faith as necessary truth. This reveals: Only the biblical foundation makes truth possible—all other conceptions are thereby not merely unnecessary but impossible.³³

In this section Cheung shows that Christian faith's truth must be not merely defended but fundamentally and comprehensively grounded—in such a way that all opposites are simultaneously excluded. This initially sounds abstract but is actually very simple once one understands the underlying thought:

1. Truth excludes error—completely

Cheung begins with a very simple but important thought: If something is true, its opposite cannot also be true simultaneously. This sounds self-evident but is highly significant when reflecting on how truth can be defended. Just as “1 + 1 = 2” does not become true only by refuting all possible false results but inherently excludes all opposites, Christian faith is likewise true: It sustains itself and makes all counterconceptions impossible.

Take an example: The mathematical statement 1+1=2 is true. This automatically means: 1+1=1, 1+1=3, 1+1=4, 1+1=5 and so on—and thus an infinite number of mathematical statements—are false.

This leads to an important point: If we want to defend a true statement, refuting every individual false alternative in detail is neither meaningful nor possible, for infinitely many exist.

It would be like attempting to expose and correct every individual error in human history—impossible.

What we need instead is a foundation so clear and strong that it inherently shows:

➞ “I am true, and everything contradicting me is therefore automatically false.”

In other words: Truth proves itself not by fighting every lie individually but by excluding everything else. A firm, true foundation makes clear: Everything not standing on it will not hold.

And precisely this is also how we should defend Christianity: not by refuting every religion and worldview individually but by showing:

➞ Only the Bible's God explains truth at all.

➞ Only his revelation sustains thinking, judging and knowing.

Everything else then falls—not because we fought it individually but because it is incompatible with the foundation.

Transferring this thought to Christian faith makes something very important clear. Suppose biblical Christianity is actually true. That means: God has truly spoken, and the Bible is truly his Word. And in this Word God also says very clearly that all other religions and worldviews do not know the true God but deviate from him or misrepresent him.

What follows?

➞ Then all non-Christian perspectives are not simply “different”,

➞ but false by logical necessity.

Why? Because two contradictory statements cannot be true simultaneously. For example, if the Bible says “Jesus is the only way to God,” another religion saying “There are many ways to God.” cannot also be right.

This is no arrogance but a consistent application of truth:

➞ If God has spoken—

➞ and if what he has said is truly truth—,

➞ then everything contradicting him cannot also be true.

This is not narrow-mindedness but simple logic. Just as “1 + 1 = 2” is correct and all other calculations yielding a different result are thereby false, God's true Word is likewise the measure of all things, and everything contradicting it cannot stand.

2. The argument's three steps

Vincent Cheung summarizes his argument in a clear, three-step line of thought. It is a simple scheme but with enormous implications:

1. Christianity is true by logical necessity.

➞ It is not merely probable or persuasive but necessary, because only the biblical worldview can explain how truth, knowledge, morality and meaning are possible at all.

2. Christianity excludes all other worldviews.

➞ For they posit other gods, authorities, moral criteria and foundations of knowledge and thereby contradict what God has said about himself.

3. All non-Christian worldviews are therefore necessarily false.

➞ They contradict not merely the Bible but the presuppositions necessary to think or know meaningfully at all.

Cheung emphasizes that point 1 is the key. If this stands—if the biblical axiom can be shown necessary—the rest follows by itself. For what is necessarily true excludes everything else. There are then no “equally entitled alternatives,” only truth or error.

3. What does this mean for our apologetics?

Vincent Cheung makes clear here that we need not claim to analyze and dismantle every individual worldview—Islam, atheism, pantheism or relativism—in detail. This would be not merely impossible in terms of time but often not particularly effective in practice. Instead we should take a different, better path: We should present the Christian worldview positively and clearly so it makes clear inherently:

• Only this worldview truly holds.
• Only this worldview is free of internal contradictions.
• Only this worldview can explain why truth, morality, knowledge and meaning exist.

If this succeeds, all other worldviews automatically fall away. Not because we refuted each individually but because the biblical foundation is so stable that everything contradicting it necessarily collapses logically.

The conversation partner can then no longer simply throw in new possibilities such as “Maybe there are also other ways ... maybe religion XY is right too ...” These “possibilities” are not truly open if biblical truth is logically necessarily true. They are then not “interesting alternatives” but excluded—through the foundation itself. And precisely this is the axiomatic approach's power: It defends faith not through a mass of arguments but through the unshakability of the starting point.

4. And what if?

Of course—when confronted with a particular worldview in conversation, it can be helpful and meaningful also to undertake a targeted refutation of this specific perspective. But this is not apologetics' foundation, merely an application.

The actual strength lies in the foundation. In a worldview sustaining itself and necessarily excluding all other perspectives logically, because it alone offers the presuppositions of truth, logic, knowledge and morality.

Cheung's argument is simple and powerful precisely for this reason:

Anyone truly wanting to defend truth need not fight every individual lie but must show truth so clearly and unambiguously that every lie is automatically excluded alongside it.

This makes biblical apologetics not weaker but invincible:

➞ What is true by logical necessity cannot be refuted.

➞ It does not merely “fare better” but is the only position able to stand at all.

Summary of section 2.2

2.2.1 Scripture as the norm of all norms: The Bible is the axiom If God has truly spoken, the Bible is no mere valuable contribution but the source of all truth. It is not the result of human research but the criterion against which everything is measured—including reason, science and experience. Anyone wanting first to examine it before believing it elevates themselves above it and thus above God himself. The Bible is the axiom: It examines everything but is itself examined by nothing.

2.2.2 The argument from indestructible consistency (coherence) The Bible is not merely true but internally perfectly coherent. It contradicts itself neither logically, morally nor theologically. Its unity expresses God's unity. It explains the world as a whole: history, language, thinking, morality; everything finds its place within it. Other systems fail through internal contradictions, and the Bible exposes them while itself remaining firm. Its coherence shows that it originates not from human hands but God himself.

2.2.3 The principle of sola Scriptura within apologetics The Reformation confessed: Scripture alone is highest authority. Apologetics must not abandon this principle. Anyone attempting first to legitimate the Bible through reason, archaeology or natural science has already installed another authority. True defense of faith begins with God's Word itself, not outside it. The axiomatic approach is therefore the only consistently biblical path: Scripture is not to be justified; it is the criterion of all justification.

2.2.4 Consequences for knowledge, morality and understanding the world If the Bible is our axiom, this concerns everything: how we know, what is right and how we interpret the world.—Knowledge: Only God's Word makes certain knowledge possible (Col 2,3).—Ethics: Only scripture objectively reveals what is good and evil (Ps 119,105).—World interpretation: Only it explains history's origin, goal and meaning (Ps 119,91). Without the Bible, humanity is left with open questions and blind spots. With it, everything becomes clear.

2.2.5 Why Christianity rather than another religion's God? Truth automatically excludes error, just as “1 + 1 = 2” excludes infinitely many false calculations. If the biblical worldview is true, all other perspectives are necessarily logically false. Apologetics therefore consists not in laborious refutation of every individual opinion but clear exposition of the true foundation. Anyone understanding it need not defend truth against every lie. They show it so clearly that all lies are thereby excluded. What is necessarily true cannot be refuted.

Reflection questions for section 2.2

2.2.1—Scripture as the norm of all norms: The Bible is the axiom

• What does it mean practically that the Bible is not measured but is itself the criterion?
• In which situations are you tempted to want to “verify” the Bible first rather than trust it from the outset?
• Why is it spiritually dangerous to grant the Bible authority only when it agrees with science, logic or feeling?
• Which biblical statements support for you the thought that God's Word stands above everything—including your thinking?

2.2.2—The argument from indestructible consistency (coherence)

• Why is the Bible's internal consistency such strong confirmation for your faith?
• How do you react when encountering supposed “contradictions” in the Bible?
• How does the Bible's coherence differ from other religious or secular systems you know?
• What does the thought that all attacks on the Bible ultimately rest on presuppositions supplied by the Bible itself say to you?

2.2.3—The principle of sola Scriptura within apologetics

• Why is it decisive to treat the Bible not as a theory but as ultimate authority?
• In which apologetic conversations have you experienced how easily one is tempted to place “neutral” criteria above scripture?
• What does it mean for your conversation that apologetics must begin with scripture rather than outside it?
• How would you explain to someone that there is no “middle way” between trust in the Bible and criticism of it?

2.2.4—Consequences for knowledge, morality and understanding the world

• How does the Bible help you understand the surrounding world more clearly, particularly regarding morality, truth and meaning?
• Where have you experienced a perspective without biblical foundation beginning to shake, for example regarding science, ethics or identity?
• What does it mean to you personally that without scripture's light, all this world's signs remain unintelligible?

2.2.5—Why Christianity rather than another religion's God?

• How does Cheung's argument help you avoid disputes over details and argue from the foundation?
• Why is it important to recognize that truth logically excludes all opposites and cannot stand “alongside other things”?
• What experiences have you had with statements such as “There are many ways to God,” and how can you respond biblically and lovingly?
• Why is the biblical worldview not merely one option among many but the condition for knowledge, logic and morality to be possible at all?
• Which statements in Cheung's argument particularly challenged or newly strengthened you?