The Trinity: A Doctrinal Summary

In the history of the Church her doctrines have been understood and organized through seven distinct yet interrelated topics or categories: Scripture, God, Man, Christ, Salvation, Church and Last Things. These distinct yet inseparably related doctrines reveal that the doctrine of the Trinity is the fundamental root from which they all come, by which they are revealed and the fruit to which they point (Rom. 11:33-36). Our knowledge of all creation and thereby our Creator and Redeemer is from beginning to end Trinitarian.

The biblical doctrine of the Trinity affirms that God is one being in three persons: Father, Son and Holy Spirit, from all eternity, and these three are the same in substance, equal in power and glory. All three persons of the Trinity are equally God, or we could say that the fullness of God is present in them, or in each person. The Father is God, the Son is God and the Holy Spirit is God. None of the three lack something that one of the others has. None of them ever started or stop being who they are (Exod. 3:14). Both the simplicity of God and his unchangeableness or impassibility are expressed in these truths. Still, none but God the Son became Man. Yes, this is, to say the least, difficult to understand! Yet, this is what God reveals about himself through his written word and indeed in all creation. Still, we would have no knowledge of this simply from creation itself, because of our sin. The Trinity’s work of saving sinners gives this knowledge.

There is no deficiency in what God does. There is a true knowledge of God revealed by God in what he has created, in all its unity and diversity. God reveals himself in and through his creation. Because of sin, though, all humans suppress the truth (Rom. 1:18) of God’s revelation of himself present in creation. Our sin consists of our unwillingness and inability to understand and respond in a God-honoring way to all the diverse realities created and that exist in a particular relationship to each other and us (Rom. 1:18-32). Everyone’s failure to admit and live righteously in the truth regarding God is their own fault. The creation is not deficient, but sinful humans are.

Apart from God choosing to have mercy upon sinful humans, they would not be saved from sin, or know God as the loving Father, Son and Holy Spirit. God’s salvation of sinners is his Triune work whereby he reveals his Triune nature and power to those upon whom he chooses to have mercy. These are the people for whom the Father sent the Son, for whom the Son lived, died, rose again and ascended into heaven, for whom the Father and Son sent the Holy Spirit, and for whom and to whom the Holy Spirit reveals the truth regarding salvation through his application to them of all that Jesus, the Son secured for them for the eternal glory of the Triune God (John 14-17). Thus, there is a diversity within the one unified work of salvation by God. God’s saving work is only rightly understood in its Trinitarian nature.

This Trinitarian work of salvation takes place in God’s creation that has been corrupted and enslaved by sin (Genesis 3; Romans 8:19-23). This Triune work destroys the devil’s work (1John 3:8). The Triune God who created time and space, the very realities that comprise the “historical realm,” has been rescuing and continues to rescue his people from their sin in every era of history, and is even rescuing history itself from sin. It is God fulfilling his covenant promise, first made to Adam and Eve in Genesis 3:15 and historically applied and progressively revealed by the Father through the Son by the Holy Spirit as he has providentially governed and guided the history of his creation.

The Triune God began this work with Adam and Eve, the first male and female, the first husband and wife, who were bound by him to one another in the covenantal union of marriage, and he has revealed that this same kind of covenantal marriage relationship is seen in his covenantal relationship with his church through Christ’s relationship to her through the Spirit that saves her from her sin and will be consummated in and through history. (Gen. 1-3; Eph. 5:21-33; Revelation 19-22).

In all this we see a unity within a vast diversity, an ability to distinguish one reality from another and in relation to another reality. The very basis or root of all human knowledge of everything in creation and that is inseparably related to the doctrines of the Christian faith in all their unity and diversity is the distinctions between, and the unity of, God the Father, Son and Holy Spirit. Still, we would have no knowledge of these matters were it not for God’s Triune work of the Son on earth paying the penalty for our sin, and releasing us from the power and presence of sin, through the power of the Spirit for the glory of the Father. Praise be to the Triune God!

David P. Smith (Ph.D.) is the author of B. B. Warfield's Scientifically Constructive Theological Scholarship (Wipf & Stock) and co author with Ronald Hoch of Old School, New Clothes: The Cultural Blindness of Christian Education Wipf & Stock). David is Pastor of Covenant Fellowship A.R.P. Church in Greensboro, North Carolina.