In a recently published collection of essays on the Trinity, Scott Swain discusses B.B. Warfield’s treatment of the doctrine of the Trinity, with particular attention to Warfield’s rejection of the language of “eternal generation.” That’s a hugely interesting and important topic, but it’s not the subject of this post per se. Instead, I want to focus on the broader point that Swain makes about Warfield’s approach, namely, that it’s a bit too pared down, that part of the reason why Warfield is ambivalent about eternal generation is that his summary of the Trinity does not include adequate reflection on what makes the divine persons distinct from another.

Warfield summarizes the biblical teaching on the Trinity in a kind of three-step process. Swain explains:

Warfield summarizes the main lines of biblical teaching on the Trinity in three points: (1) “there is but one God,” (2) “the Father and the Son and the Spirit is each God,” and (3) “the Father and the Son and the Spirit is each a distinct person.” “When we have said these three things,” [Warfield] insists, “we have enunciated the doctrine of the Trinity in its completeness.” (p. 33).

As Swain points out, this is a fairly standard way of summarizing the Bible’s teaching on the Trinity among evangelicals. It’s even given pictorial representation in the widely used image above. But it leaves unexplained just what makes the Father, Son, and Spirit “each a distinct person.” It’s not that the summary is unhelpful or untrue, but it’s claim to “completeness” is suspect.

So, what would it look like to supplement Warfield’s approach with a bit fuller summary, but one that can still justifiably be considered a summary and not an attempt to be exhaustive? How would you summarize the biblical teaching on the doctrine of the Trinity? For what it’s worth, here’s my shot (notice that the first three points track with Warfield’s):

1. God is one. The New Testament (Mark 12:29; 1 Cor. 8:4, 6; 1 Tim. 2:5), no less than the Old Testament (Deut. 6:4; Exod. 20:1-2; Isa. 45:6), affirms that there is only one God. While there may be other spiritual beings (angels, demons, and human souls), there is—and can only be—one transcendent and immanent Creator and Lord of heaven and earth.
2. Each of the persons is divine. Once the first person, the Father, is distinguished in the New Testament, his deity is assumed throughout. The deity of the Son is demonstrated by the fact that the attributes, actions, names, titles, and worship of God are ascribed to him. Similarly, the Holy Spirit is named as a distinct person alongside the Father and Son (e.g., Matt. 28:18-20; 2 Cor. 13:14) and his deity is shown by his divine attributes and actions.
3. The persons are really distinct from one another. The three are not simply successive manifestations or modes of revelation to humanity. They are simultaneously existing persons with real relations to one another (think of Jesus’ baptism, Matt. 3:13-17). And these distinctions are not merely ad hoc arrangements in redemptive history but mark out real distinctions in eternity. These distinctions are made evident by the personal names given to each of the three in Scripture: Father, Son, and Holy Spirit. The Father is eternally the Father of the Son; the Son is eternally the Son of the Father; and the Holy Spirit is eternally the one “spirated,” or breathed out, by the Father and Son. The three relate to one another and love one another in the eternal glory of God’s own life (John 17:5)
4. Because God is one, he acts as one. The three divine persons act as one in redemptive history.  All of the actions of God in the world—creation, providence, redemption, and judgment—are attributed to each. They are not three separate beings doing three separate but harmonious things. They each act in the others’ actions. The Holy Trinity acts in an inseparable and indivisible manner. To pick just one example, consider the act of creation. The Father creates through his Word (John 1:1-3; cf. Gen. 1:3) and Spirit (Gen. 1:2).
5. Some divine attributes or actions are appropriated to particular divine persons, but not in such a way as to exclude the others. So, for example, we might say that the Father is our creator, the Son is our redeemer, and the Spirit is our sanctifier. But because of the previous point (that God acts in an indivisible way in all of his actions), this appropriation is only a manner of speaking. All three persons are the creator, redeemer, and sanctifier. The appropriation of certain attributes to certain divine persons only serves to highlight their unique personal identity. For example, the Son is referred to as the Word or Wisdom of God in Scripture, not because he alone possesses the divine attribute of wisdom, but because this name highlights his unique personal property of being from the Father, as a word proceeds from a mind.
6. Still, each person participates in the indivisible action of God in a manner that is appropriate to his personal identity. In any act of the Triune God in the world, there is only one action. But there are three modes of action corresponding to the three persons active within, so to speak, that one action. Simply put, the Father acts as Father in the inseparable action of the Trinity, the Son as Son, and the Spirit as Spirit. The early church Fathers, following the New Testament pattern, often spoke of these modes of action by means of distinct prepositions: the action of God comes from the Father, through the Son, and by the Spirit (see, for example, 1 Cor. 8:6). And, of course, because the Son alone became incarnate as a human, the actions that he carries out humanly are exclusive of the Father and Son. The point here is that everything that God does divinely, he does as Father, Son, and Spirit—in essentially indivisible but personally differentiated action.