The objection
If “God” designates first the Father, then divine being and finally Father, Son and Spirit, Trinitarian doctrine seems to evade contradiction through a shift of meaning.
1. John himself distinguishes the statements
John 1,1 says that the Word was with God and the Word was God. The first statement distinguishes the Word from the one with whom it is. The second attributes deity to the Word. John does not first separate two persons only to make them one person again in the next clause. He distinguishes their relationship while confessing the Word's deity.[1]
This is no retrospective trick of dogmatics. Dogmatics needs the distinction precisely because the text says both. “With God” answers a different question here from “was God”: With whom was the Word? And what is the Word in its being?
2. Being designates no material
By “being” we mean what God is: his uncreated, eternal, undivided deity. It is no material from which three persons consist and no fourth reality above them. Nor is deity a genus under which several divine instances fall. Father, Son and Spirit do not each possess their own portion of the same material.
“Person,” by contrast, designates the really distinguished Father, Son or Spirit. The Father is not the Son; the Son is not the Spirit. These distinctions are eternal and belong to God's own life. They do not arise only when God shows himself to humans.
“Nature” here likewise designates the one deity. In developed Trinitarian terminology, “hypostasis” names the concrete person; “subsistence” emphasizes their real existence as distinct from a mere attribute or appearance. “Relation” means a relationship, such as fatherhood toward the Son. This relationship distinguishes the persons without dividing deity. “Substance” requires particular care: The word can designate essence or concretely existing being. Thomas already explains this ambiguity. The same translation must therefore not be inserted uncritically into every historical text.[3]
3. The same being does not mean interchangeable persons
One can truthfully say: The Son is omniscient; the Father is omniscient. One cannot say: The Son is the Father. Omniscience belongs to divine being. Fatherhood designates the particular relationship to the Son. Thomas therefore explains that personal names and designations of being assert different things without naming two constituents in God.[2]
The helpful brief distinction “What?” and “Who?” is intended to achieve precisely this. It is no complete description of God's inner life. But it prevents us from silently turning “The Son is God” into “The Son is the Father.”
4. Context determines usage
In John 17,1–3, “God” designates the Father addressed. In John 20,28 Thomas addresses Jesus as his God. The same evangelist transmits both. An interpretation automatically turning every use of “God” into “exclusively the Father and never the Son” already inserts its conclusion into the dictionary.
We therefore do not change the word's meaning as needed. We disclose whether a sentence designates a person or asserts their deity. Only with this clarity can a logical objection even be examined. Anyone defining “God” from the outset as “one single divine person” has already excluded the Trinity before presenting an argument against it.
Biblical texts in context
Sources and further study
- Robert L. Reymond, A New Systematic Theology of the Christian FaithCh. 8, section “John 1:1,” pp. 299–301: the Word's distinction from the Father and his deity.
- Thomas Aquinas, Summa theologiaeI, q. 29, a. 4; q. 39, a. 1–4: persons, being and usage of the divine name.
- Thomas Aquinas, Summa theologiae, I, q. 29, a. 2 and 4Distinction of essence, hypostasis and subsistence; the relational meaning of the divine personal name.