Here’s how Geerhardus Vos articulates the core affirmations of the orthodox doctrine of the Trinity:
- There is only one divine being. Scripture expresses itself decisively against all polytheism (Deut 6:4; Isa 44:6; Jas 2:19).
- In this one God are three modes of existence, which we refer to by the word “person” and which are, each one, this only true God. In Scripture these three persons are called, Father, Son, and Holy Spirit.
- These three persons, although together the one true God, are nevertheless distinguished from each other insofar as they assume objective relations toward each other, address each other, love each other, and can interact with each other.
- Although these three persons possess one and the same divine substance, Scripture nevertheless teaches us that, concerning their personal existence, the Father is the first, the Son the second, and the Holy Spirit the third, that the Son is of the Father, the Spirit of the Father and the Son. Further, their workings outwardly reflect this order of personal existence, since the Father works through the Son, and the Father and Son work through the Spirit. There is, therefore, subordination as to personal manner of existence and manner of working, but no subordination regarding possession of the one divine substance.
- The divine substance is not divided among the three persons as if each possesses one-third. Neither is it a new substance beside the three persons. Finally, neither is it an abstraction of our thinking in a nominalistic sense. But in a manner for which all further analogy is lacking, each of these persons possesses the entire divine substance.
Geerhardus Vos, “The Trinity,” chapter 3 of Theology Proper, vol. 1 of Reformed Dogmatics, ed. Richard B. Gaffin, trans. Annemie Godbehere (Bellingham, WA: Lexham Press, 2013), 38–39.
By the way, today is Vos’s 151st birthday. In honor, Logos Bible Software just posted a 14-volume collection of Vos’s works on Pre-Pub. They’re also working on the first ever English translation of Vos’s Reformed Dogmatics, from which the above quotation comes.