The story of Christmas is a multi-layered story of adoption. At the most surface layer, of course, it is the story of a righteous man named Joseph adopting his wife Mary’s son as his very own. After Mary was betrothed to Joseph, she was discovered to be pregnant with someone else’s child, and so Joseph planned to divorce her quietly lest she be exposed to public shame (Matt. 1:18–19). However, an angel of the Lord revealed to Joseph that he should take Mary for his wife, that her son was conceived by the Holy Spirit in fulfillment of God’s promise in Isaiah 7:14, and that Joseph was to adopt the virgin’s son by naming him Jesus (“salvation”) because the son would save his people from their sins (Matt. 1:20–23). Joseph obeyed God by marrying Mary and naming the child Jesus, thus adopting her son as his own (Matt. 1:24–25).[1] On a deeper level, however, I will show that this divine giving of a son is the consummation of God’s own adoption of sons. Christmas is about adoption.
1. France explains that “these two actions” — receiving Mary as his wife and naming the son — “completed the legal adoption of Jesus as Joseph’s son.” R. T. France, The Gospel of Matthew. NICNT (Grand Rapids: Eerdmans, 2007), 58.
God Sent Forth His Son
Galatians 4:4–5 proclaims one primary assertion supported by five subordinate clauses, as the emphasis shows below:

This phrase is not only the essence of both Christmas and Easter, but the very essence of the whole Bible. The message of all the Scriptures can be unpacked from the statement: “God sent forth his Son.” All the promises and prophecies and shadows and types of Scripture can be related to the truth that God sent forth his Son. The depths of divine love and the ultimate answer to every human need is seen in the truth that God sent forth his Son. God gave Jacob visions and sent Joseph dreams and spoke to Moses from a burning bush and gave Israel the law on tablets of stone and sent them prophets to speak his word, but the most decisive and radical and wonderful intervention by God into human history is that God sent forth his Son. The message of the Old Testament points to it, and the message of the New Testament flows from it. The human race never received a higher gift than this: “God sent forth his Son” (Rom 8:32).
When God Sent His Son
The five subordinate clauses serve to set forth the time, the manner and the purpose of God sending forth his Son. The first supporting clause gives the when; the second and third, the how; and the fourth and fifth, the why. First, God sent forth his Son when the fullness of time had come. This elegant phrase, “the fullness of time,” requires some explanation. It is certainly a way of saying that it was the right time, and it was a way of saying that the time had been fulfilled as Jesus proclaimed in Mark 1:15. But there is a larger story behind that phrase, “the fullness of time.”
This story unfolded over thousands of years and began with God’s adoption of a human son at creation when God made, named, and entered into covenant relationship with “Adam, the son of God” (Luke 3:38). When Adam sinned, he brought God’s curse upon all creation, to which God responded with his promise to reverse the curse through the male “seed of the woman”—that is, a son (Gen. 3:15). Why was Jesus born at this specific time? Why not earlier or why not later? There was something significant about this point in redemptive history, and it becomes especially clear from the immediate context of the larger argument Paul is making to the Galatians. His point is that the law of Moses had done its work. The Mosaic covenant had served its temporary purpose. You see this especially in Galatians 3:24: “So then, the law was our guardian until Christ came, in order that we might be justified by faith” (emphasis added). The law had been doing the work of the guardian for all these hundreds of years since Moses received it at Sinai, and now it was time to dismiss the guardian. God’s people were approaching the time when they would be taken out from under the law which had done its work of revealing sin and maintaining a distinct people and so serving the promises made to Abraham. At long last, it was time to send forth the long-expected son.
Earlier in redemptive history, God had developed his initial redemptive promise of the seed of the woman to Abraham, Isaac and Jacob. He redeemed Israel, his adopted “firstborn son” (Exod. 4:22), from slavery in Egypt and gave his law-covenant to preserve them for 1,500 years through all their failures until the law-covenant had fulfilled its intended purpose. The promise is primary, and the law is subordinate to the promise. Moses serves Abraham until Abraham fathers the promised seed. Therefore, when the fullness of time had come, God sent forth his Son. The promised Son being sent forth in the fullness of time by God as the “last Adam” (1 Cor. 15:45) is the culmination of God’s two adoptions, that of the first Adam and that of Israel as a second Adam. On a deeper level still, this giving of a Son is for the fulfillment of the Father’s eternal purpose to adopt a multitude of sons.
How God Sent His Son
Second, Paul uses twin participles (gegomenon) to highlight how God sent his Son. God sent forth his Son born of woman, born under the law. This is the high and holy mystery of the Incarnation. In the birth of Jesus, God the Son forever became a member of the human race. Echoing Genesis 3:15, Paul says Jesus was born of a woman. This affirms his true humanity. Job 14:1 says, “Man, who is born of a woman, is few of days and full of trouble.” The divine Son is truly divine, sent from God, and truly man, born of a woman. Of this truth, J. I. Packer writes:
It is here in the thing that happened at the first Christmas that the profoundest and most unfathomable depths of the Christian revelation lie, the Word was made flesh, God became man, the divine Son became a Jew, the Almighty appeared on earth as a helpless human baby, unable to do more than lie and stare and wiggle and make noises, needing to be fed, and changed, and taught to talk like any other child. And there was no illusion or deception in this. The babyhood of the Son of God was a reality. The more you think about it, the more staggering it gets. Nothing in fiction is as fantastic as is this truth of the Incarnation.[2]
2. J. I. Packer, Knowing God (Downers Grove, IL: InterVarsity, 1973), 53.
When we ponder that God sent forth his Son born of a woman, we learn something of the love and condescension of God. God did not have to become a man, to be born of a woman, to become a baby. There was nothing in us that deserved such a loving and sacrificial act. In fact, we deserved to be utterly forsaken by God. Yet in his great love for us, he chose not only to visit us, but to become permanently one of us. This is what the Son of God did when he was born of a woman. He stooped down to us in the ultimate display of loving condescension by humbling himself and becoming a creature: a man. There has never been a descent such as Jesus’s descent from the highest place above heaven to what Paul called “the lower regions, the earth” (Eph. 4:9). He came down, was born a baby boy and lived in poverty and suffering and rejection as a human being. Second Corinthians 8:9 succinctly captures this condescension: “For you know the grace of our Lord Jesus Christ, that though he was rich, yet for your sake he became poor, so that you by his poverty might become rich.”
Jesus was born under the law (Gal. 4:4). This fact further demonstrates the love and condescension of God in the Incarnation. To be born under the law is to be born into a cursed and broken world, under the curse of the law. For all of us, being born under the curse includes being born as sinful creatures, but Jesus is the exception. He kept the law perfectly on our behalf. He never sinned but always did what was pleasing to his Father. It was for our sake that he was born under the law, and God sent him forth, as we sing during this season, “to make His blessings flow far as the curse is found.”
Why God Sent His Son
This brings us, third, to the twin purpose clauses which highlight why God sent forth his Son. The Son was sent “to (hina) redeem those who were under the law, so that (hina) we might receive adoption as sons.” Here is the purpose of it all. This is the mission of Christmas. The goal of the Lord Jesus in the Incarnation is the redemption of those who were under the law. To redeem means to deliver by purchasing. Jesus was born to purchase a cursed people out of slavery to sin. Paul has just said that “Christ redeemed us from the curse of the law by becoming a curse for us” (Gal. 3:13). Jesus was born to die, and he died so that spiritually dead sinners might be made to live.
In another reflection on the Christmas story, Paul writes that “Christ Jesus came into the world to save sinners” (1 Tim. 1:15). The Son came to pay a price. God sent forth his Son to redeem those under the law. We all have sinned, and so we remain eternally cursed unless one bears the curse for us and pays the penalty demanded by God’s law and stands in our place providing a righteousness for us that we do not have, desperately need, and cannot earn. It is the good news of Christmas that a savior was sent into the world to do this very thing. His redemption paid the price and bought and gave himself ownership of exactly what he was paying for—his sheep, his people, his elect whom he came to redeem. Amazingly enough, this unfathomable particular redemption is not an end in itself but a means to a further end, and that is the adoption of the redeemed as sons of God. God sent forth his Son in order to redeem those who were under the law, in order that we might receive adoption as sons. The adoption that belonged to Israel (Rom. 9:4), through the giving of God’s true Son, becomes the possession of all who are now united to the true Son by faith in him (Rom. 8:14–15, 23; Eph. 1:5).
Conclusion
When the fullness of time had come, God sent forth his Son. Jesus was born of a woman, born under the law, to redeem those who were under the law, so that we might receive adoption as sons. He not only bought us, but he made us sons of God. He became born of a woman so that we would become born of God. As the adopted child of Joseph he died to make us the adopted sons of God. We are put into God’s family through faith in his Son. Those who were his enemies are now his sons, not by anything we have done, but by what he has done in sending forth his Son. All who trust in the Son for salvation are now beloved, adopted as sons. This is the good news of Christmas for an orphaned world desperately in need of adoption into the household of God through faith in his Son.