God is Father, Son, and Holy Spirit. He is eternally, internally Triune, and when he acts outside himself, he acts in a way consistent to his being—from the Father, through the Son, by the power of the Holy Spirit.
In the gospel, God reveals himself as Father, Son, and Holy Spirit. As such, the Trinity is the real content and conceptual framework of the Christian faith. The Father, Son, and Holy Spirit are united in being and differentiated by their eternal relations: the Father eternally begets the Son; the Son is eternally begotten of the Father; the Holy Spirit is the bond of their love. When God acts outside himself in creating and saving, the persons act in unity—from the Father, through the Son, by the power of the Holy Spirit.
The God of the Gospel
The Triune God is the God of the gospel—the ultimate reality unveiled in the good news of the Lord Jesus Christ.1 In the gospel, God reveals himself as Father, Son, and Holy Spirit. As such, the Trinity is the real content and conceptual framework of the Christian faith. Moreover, the church’s saving knowledge of God occurs through reconciliation to him in the only begotten Son of the Father by the power of the Holy Spirit.
Christ’s instruction for baptism in Matthew 28:19 demonstrates the essential connection between the Trinity and the gospel.2 Christians are commissioned to baptize “in the name of the Father, Son, and Holy Spirit,” not as a mere formality, but because of the nature of our salvation. The Lord Jesus defines God as Father, Son, and Holy Spirit. In doing so, God heralds himself to us by naming himself for us, thereby revealing his eternal being. He is Father, Son, and Holy Spirit, and our baptism in his name signifies our participation in his loving, Triune communion. The gospel is the gracious act of the Triune God—the Father sending the only begotten Son to become human for us and our salvation, so that in the power of the Holy Spirit we might participate in his eternal life. In our baptism, we are united with Christ in his death and raised to his life (Rom 6:4), the life of the Trinity. The risen Christ then sends his church to proclaim this gospel, an open invitation for all to join our fellowship in the Triune life (1Jn 1:3) through union with him in his death and resurrection.
A Quick Word about Words
As we describe the God of our salvation and proclaim him to one another, the nature and limitations of language present challenges for our theological articulation. Every word we use to speak of God already has meaning in a different context. For example, when you hear the word “Father,” you have a preconceived notion of its meaning related to your understanding of human fatherhood. When we use “Father” to refer to God, we must conform our understanding of the word to align with its divine reference and maintain reverence for God’s holiness. God reveals himself to us in familiar terms, but we must hold our understanding of those terms loosely and allow God to define himself for us, acknowledging his eternal, infinite goodness and our own finitude. We should use theological language with an expectation that God will reveal himself in our speaking and give us an understanding of the reverence appropriate for his presence.
The Union and Communion of God’s Being: Eternal Relations
God’s eternal life is “active and full.”3 The Father, Son, and Holy Spirit are the eternal fellowship of abundant life and love, not by willing choice, but as the very essence of God’s being. John reminds us twice in 1 John that “God is love” (4:8, 16), not as a statement of how God acts, but of who God is. God is not only loving toward us; God is love in his internal, eternal being. The Father eternally loves the Son. The Son is eternally beloved of the Father. The Holy Spirit is the bond of the Father and Son’s loving fellowship. The Triune God’s eternal relations (sometimes called “processions”) of love are the subsistence of his being and what differentiate the Father, Son, and Holy Spirit.
The Bible uses two parallel language motifs to describe the eternal relations of God’s being—love and begotteness. Readers see the eternal communion of God revealed in terms of love at the baptism of Christ. Matthew tells us that at Jesus’s baptism, “immediately [Jesus] went up from the water, and behold, the heavens were opened to him, and he saw the Spirit of God descending like a dove and coming to rest on him; and behold, a voice from heaven said, ‘This is my beloved Son, with whom I am well pleased’” (3:16–17). The Father identifies Jesus as his “beloved Son.” The Father loves the Son, and the Son is loved of the Father—his Beloved. The Gospel of John uses this same language of begotteness to describe the relationship between the Father and the Son. The familiar verse John 3:16 teaches that “God so loved the world, that he gave his only Son.” “Only Son” is a translation of the Greek term monogenes that underscores the distinct relationship of begotteness between the Father and the Son. The Father eternally begets the Son, and the Son is eternally begotten of the Father.
The biblical authors describe the eternal relation between the Father and the Son by highlighting the themes of love and begotteness. The Father, by virtue of his divine Fatherhood, eternally gives life and love to the Son, begetting the Son as his very same being. While human fatherhood begins at a point in time and confers some measure of hierarchy, God’s Fatherhood is eternal with no difference in being outside of the relation itself. Likewise, the Son is eternally beloved and begotten of the Father—one in being with him. While human sonship begins at a point in time and involves some measure of subordination, God’s Sonship is eternal with no difference in being outside of the relation itself.
Like the Triune fellowship mentioned above, the relationship of begetting/begotteness does not occur by willing choice. The Father does not choose to beget the Son; if he had, it would mean the Father existed prior to the Son and the Son was his creation. Begetting describes who God is, not what he does. God’s being eternally exists as the communion of the Father and Son. The early church Fathers summarized this teaching for the church in the Nicene Creed, writing that the Lord Jesus Christ is the “only begotten Son of God, begotten from his Father before all ages, Light from Light, true God from true God, begotten not made, of one being with the Father.”
The Holy Spirit is the fellowship of the Father and the Son’s love. He proceeds from the Father and the Son eternally. At Jesus’s baptism, the Holy Spirit descends from the Father to the Son. The movement of the Holy Spirit from the Father to the Son is indicative of his eternal relation as the communion of the Father and the Son. The Holy Spirit eternally participates in the loving and living communion of the Father and the Son as he proceeds from them both. He is one in being with the Father and the Son and differentiated only by the relation of procession. He is not subordinate to or distinct from the Father and Son in nature.
The Father, Son, and Holy Spirit are differentiated by their eternal relations yet one in their being. Or as the familiar and true adage goes: the Trinity is three persons (hypostasis), yet one being/nature/essence (ousia). Because of how we use it in our created context, “person” can be misleading depending on how we define it. We must be mindful of the conceptual framework we bring to our understanding of “person” in its Trinitarian sense.
If we impose on the Triune persons our presuppositions about what differentiates human persons, Trinitarian error will be inevitable. Human persons are differentiated in at least three relevant ways: by (1) space—we have separate bodies, (2) consciousness—we have separate minds, and (3) volition—we have separate wills. If we assume those differentiations of the Father, Son, and Holy Spirit, we will undermine their unity of being and functionally hold to tri-theism instead of Trinitarianism.
Differentiating the persons of the Trinity in terms of space is not possible because God is spirit (John 4:24). In terms of mind, God’s knowledge is shared in the same way as his being. God shares his mind/self-knowledge in the communion of the Father and the Son—as Jesus said, “No one knows the Son except the Father. No one knows the Father except the Son” (Matt 11:27). The Spirit participates in the knowing communion of the Father and the Son, as “no one comprehends the thoughts of God except the Spirit of God” (1Cor 2:11). Thus, the mind of God is shared in the same way as his being—from the Father to the Son in the communion of the Holy Spirit.
God’s will is also shared from the Father to the Son by the Holy Spirit. God’s purposes and actions follow the same contours of the Trinity’s eternal communion. Jesus explains, “For whatever the Father does, that the Son does likewise. For the Father loves the Son” (John 5:19–20). In other words, what willing act the Father does, the Son does also because of the Father’s love of the Son. So it is with the Holy Spirit. He can reveal the will of God because it is his own (Col 1:9, Rom 12:1–2).
Neither body, nor will, nor mind separate the Father, Son, and Holy Spirit. The eternal relations alone differentiate the persons of the Trinity.
The Union of God’s Actions: Inseparable Operations
God is eternally, internally Father, Son, and Holy Spirit. When the Triune God acts outside of himself, he acts in a way consistent with his being—from the Father, through the Son, by the power of the Holy Spirit. The Bible reveals this Triune relational pattern in God’s creating and saving actions.
In creation, the Father creates through the Son in the power of the Spirit. In Genesis 1, God the Father speaks to create all things.4 He is the author of creation—“the maker of all that is seen and unseen,” as taught in the Nicene Creed. When John explains the Genesis 1, he teaches that all things were created through the Word, who is the eternal Son of God (John 1:3); thus, the Son is the Word spoken of the Father through which he creates. Further, Genesis tells us the Spirit of God hovered over the waters from which all life emerges (Gen 1:2). The Spirit’s hovering indicates his power making actual or effective the Word spoken of the Father to give life. In this way, there is no creating activity of the Father that does not occur through the Son in the Spirit. The Father, Son, and Holy Spirit are as inseparable in their external acts of creating as they are in their internal being.
Likewise, in salvation, the Father saves through the Son in the power of the Holy Spirit. When Paul recounts the Trinitarian framework of God’s saving activity in Ephesians, he begins by praising the Father who authored the plan of salvation before the foundations of the world (Eph 1:3–4). Specifically, the Father planned for the church to be adopted to himself through his Son. To accomplish this work, the Father sent the Son to become human and save us (John 3:16). The Father authors our salvation, and he accomplishes our salvation through the Son.
The Son, who is one with the Father eternally and sent by the Father in history, is the agent of our salvation. He accomplishes our salvation in the incarnation. God blessed us with his grace “in the Beloved” (Eph 1:6), who became human to save us through his life, death, resurrection, and ascension. Through his sacrificial, substitutionary death, Christians have “redemption through his blood, the forgiveness of our trespasses” (Eph 1:7). Through his resurrection and ascension, God “made us alive together with Christ . . . raised us up with him and seated us with him in the heavenly places” (Eph 2:5–6). Through the Son’s descent into our humanity, his vicarious obedience unto death, and his ascent out of the grave to the right hand of the Father, Christians have received adoption “as sons through Jesus Christ” (Eph 1:5). By the salvation wrought in Christ, we are welcomed into sonship in the incarnate Son.
The Holy Spirit, who proceeds from the Father and Son, is sent of the Father and Son to make actual and effective in the church the salvation accomplished in Christ. The Spirit indwells believers so that they are “sealed with the promised Holy Spirit” (Eph 1:13), uniting them to Christ in his death and resurrection. According to Romans 8:11, “If the Spirit of him who raised Jesus from the dead dwells in you, he who raised Christ Jesus from the dead will also give life to your mortal bodies through his Spirit who dwells in you.” In the same way the Spirit brought life in creation through the agency of God’s Word, the Spirit brings life to our mortal bodies through the agency of Christ according to the plan of the Father. As a result, we are saved by the united work of the Triune God as the Father acts in the Son through the power of the Spirit.
The Church’s Communion with God: Nature and Mission
The eternal life given to the church in salvation is participation in the loving fellowship of the Father, Son, and Holy Spirit. Just before Jesus’s crucifixion, he prays to the Father for his disciples, present and future, that “the love with which you have loved me might be in them and I in them” (John 17:26). Jesus prays that we might join the Trinitarian communion of love by receiving the eternal love with which the Father has loved the Son. We receive the love of God through his grace in “the Beloved” (Eph 1:6) and in the “fellowship of the Holy Spirit” (2Cor 13:14), who is the bond of love between the Father and the Son. This is the glorious mystery of our salvation, that we who “were far off have been brought near by the blood of Christ” (Eph 2:13) to receive the eternal love of the Father in him. In Christ we have his life and have it abundantly (John 10:10). Our salvation and the gospel we proclaim cannot be understood apart from a right understanding of God’s eternal Triunity.
The church goes on mission by proclaiming Christ and inviting others to join us in communion with God. We who have beheld Christ now preach him to the world that, by believing in him, they too might have the eternal, abundant life of God. As John explains in his epistle, “that which we have seen and heard we proclaim also to you, so that you too may have fellowship with us; and indeed our fellowship is with the Father and with his Son Jesus Christ” (1Jn 1:3). As the church participates in God’s mission by preaching the gospel, God’s life and love spread across the globe as people from “all nations” are baptized into the communion of God “in the name of the Father, Son, and Holy Spirit” (Matt 28:19). The nature and mission of the church is grounded in the Triune God. His being provides the conceptual framework of the church’s faith, and he reveals himself—Father, Son, and Holy Spirit—as we proclaim the gospel. The Triune God is the God of the gospel—the ultimate reality unveiled in the good news of the Lord Jesus Christ.
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Sanders, Fred. The Deep Things of God: How the Trinity Changes Everything. 2nd ed. Wheaton: Crossway, 2017.
Sanders, Fred. The Triune God. Michael Allen and Scott R. Swain, eds. Grand Rapids, MI: Zondervan Academic, 2016.
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