As Protestants, we’re passionate about justification. As evangelicals, we’re passionate about regeneration—being “born-again Christians.” As Wesleyans, we’re passionate about sanctification. But as Christians, we ought to be passionate about adoption. J. I. Packer celebrated adoption as “the highest privilege that the gospel offers.”
It’s one thing to know that the Judge has declared us righteous or even made us righteous. It’s another thing to know that the Judge has stepped down from his bench, taken us by the hand, and led us over to the adoption court. What a judge! A judge who not only declares us “not guilty” at his own expense—the death of his only begotten Son—but also invites dead dogs to come home, eat at his table always, and call him “Our Father.”
It is in part because the gospel of adoption is so important that we need to be careful in our teaching on what it means for God to be “the Father.” The good news that God can become “Our Father” through Christ depends on God first being “the Father” of Christ, his only Son, before all worlds. God is “the Father” in eternal relation to the Son (eternal generation) before he becomes “Our Father” by sending the Son into the world to make us sons through union with him (adoption).
First, God is “the Father”
In the Apostles’ Creed, we confess, “I believe in God the Father Almighty.” It’s easy to jump to speaking about how God is a father towards us. But the Creed is not making a general statement about God’s fatherliness. It is not primarily focused on God’s relation to his creation as a caring father. Before we speak about God as “our Father,” we must confess that God is “the Father” apart from his creation.
Foundational to the Christian faith is the belief that God is an eternal Father because he eternally begets a Son in his image. He is and always has been the Father. He would be the Father even if he did not have creatures to relate to in a fatherly way. This is because he has always had a Son. God eternally exists as Father, Son, and Spirit—one God in three persons.
Christians make a claim about God’s eternal fatherhood that Jews cannot make from OT revelation alone, since the Trinity is revealed in the gospel. We know that God is the Father because “God so loved the world, that he gave his only begotten Son” (Jn. 3:16; cf. 1 Jn. 4:9). If God has a Son to send, then he is Father, not just fatherly in his relation to creation or to Israel, but eternal Father in relation to the Son whom he begets before all worlds. Nothing is more central to our faith.
The first person of the Trinity is named “the Father” because he eternally begets or generates the Son, not because he acts as a father in relation to creation.
As the Nicene Creed teaches us to confess, Jesus Christ is “the only-begotten Son of God, begotten of the Father before all worlds.” Since he is “begotten, not made,” the Son is “of one substance with the Father.” This is the doctrine of eternal generation. The first person of the Trinity is named “the Father” because he eternally begets or generates the Son, not because he acts as a father in relation to creation. We begin with God’s eternal relation to the Son whom he begets. The eternal sonship of the second person of the Trinity, then, is the foundation for our adoption as sons through him.
In his refutation of “those who tamper with the faith of the Gospel by denying, under the cloak of loyalty to the One God, the birth [i.e., generation or begetting] of God the Only-begotten,” Hilary of Poitiers argues that “the very centre of a saving faith is the belief not merely in God, but in God as a Father; not merely in Christ, but in Christ as the Son of God; in Him, not as a creature, but as God the Creator, born [i.e., generated or begotten] of God” (On the Trinity, 1.16–17). This is what we confess in the great Christian creeds.
Then, God is “Our Father”
In the second article of the Apostles’ Creed, we confess that the “only Son” of the Father was “conceived by the Holy Spirit, born to the virgin Mary.” “For it was to this end,” wrote Irenaeus, “[that] the Son of God became the Son of man, that man, having been taken into the Word, and receiving the adoption, might become the son of God” (AH 3.29.1). Christ redeemed us “so that we might receive adoption as sons” (Gal. 4:5). “To all who did receive him, who believed in his name, he gave the right to become children of God” (Jn. 1:12). Through Jesus Christ, “the Father” has become “Our Father” in a new way.
We are adopted sons of the Father through union with the eternal Son of the Father.
We become sons of God when the Father sends the Spirit into our hearts to unite us to the Son. “You have received the Spirit of adoption as sons, by whom we cry, ‘Abba! Father!’ The Spirit himself bears witness with our spirit that we are children of God” (Rom. 8:15–16). We are adopted sons of the Father through union with the eternal Son of the Father. We are sons of the Father through participation in Christ’s eternal sonship. “He predestined us for adoption as sons through Jesus Christ, according to the purpose of his will” (Eph. 1:5). “For in Christ Jesus you are all sons of God, through faith” (Gal. 3:26).
Because of the incarnation, “the Father”—the eternal Father of the Son—can become “Our Father.” The Son of God became the Son of Man so that the sons of men could become the sons of God. “See what kind of love the Father has given to us, that we should be called children of God; and so we are” (1 Jn. 3:1).
