Born Under the Law to Redeem Those Under the Law

First Sunday after Christmas| Galatians 4:1-7| Pastor James Preus| Trinity Lutheran Church| December 28, 2025

He whom the sea And wind obey

Doth come to serve the sinner in great meekness.

Thou, God’s own Son, With us art one,

Dost join us and our children in our weakness.

(O Jesus Christ, Thy Manger Is, P. Gerhardt, TLH 81:2)

Christmas is the celebration of God becoming a man. Yet, it is not just that He became a man, but how He became a man. God could have formed a man of dust and joined that man’s nature to His own in a personal union, created fully man and ascended into heaven without showing any bit of humility. Being humble is not essential to the nature of man. Christ is a man today, yet He enjoys His exalted state. Yet, Christ was not just made a man, but He was born a man, born of a woman, born under the Law. Christ did not need to be born under the Law. But that is how He became a human. And He did this to redeem us from the curse of being under the Law. He does not only share our human nature, but He shares our burden, our weakness, our curse. Jesus is born under the Law for us.

But what does it mean to be under the Law? St. Paul explains that under the Law an heir is no different from a slave, but is under guardian and manager until the time appointed by his father. And we at one time, though we are heirs of everything, were enslaved to the elementary principles of the world. By elementary principles, Paul means the outward strictures of the Law. To those under the Law, the Law is an outward thing. It tells you what to do. But it gives you no power to do it.

It is not that the Law is bad. The Law is good. It expresses God’s holy will. And as an outward thing, it is very useful. It keeps the slave in check, so that he does no harm, but rather is useful. It keeps the child-heir on the property, keeps him from running off. The Law is a good manager. But the Law cannot make a slave an heir. It cannot even make an heir an heir. It only tells you what to do outwardly, but it cannot change your heart. And since it is your very heart that will be judged, the Law does nothing to help you on Judgment Day.

And this actually is where we find the Law most useful. The reason those under the Law are incapable of keeping the Law is because they are sinners. They are corrupted by sin in their hearts. The imagination and desires of their hearts are only evil continually. And so, the Law only ever exposes them as sinners. This is why St. Paul says that no one will be justified by works of the Law, because through the Law comes knowledge of sin (Romans 3:20; Galatians 2:16). Now, some will argue that Paul only means the Mosaic ceremonial law, like circumcision and sacrifices, but that a person must still be justified by his own works of the moral law. But Paul makes it clear that by law, he means the moral law as well, he means that law which exposes a sinner as a sinner (Romans 3:20). That is why he writes in Galatians 3, “Scripture imprisoned everything under sin, so that the promise by faith in Jesus Christ might be given to those who believe.” (vs. 22). The Law exposes sin. That is how it is most useful. It does not make you an heir. Rather, those who are under the Law and who fail to do what the Law requires are cursed. The Law reveals this curse.

Yet, when the fulness of time had come, God sent forth His Son, born of woman, born under the law, to redeem those who were under the law, so that we might receive adoption as sons (Galatians 4:4-5). Christ, God’s own Son, not only became a man, but He was born under the law. Now, this does not mean that Christ was born a sinner. He was born of the Virgin Mary and inherited no sin. He never did sin, nor could He sin. Yet, He still humbled Himself under the burden of the Law and obligated Himself in human flesh to obey the same strictures of the Law which make every man born of woman a slave.

We see this at just eight-days-old he is circumcised according to the Law. Then, at forty-days-old He is presented at the temple according to the Law. Yet, it was not just the ceremonial, Mosaic Law that Christ fulfilled. He fulfilled the whole law, as St. Paul writes in Galatians 5, “The whole law is fulfilled in one word: ‘You shall love your neighbor as yourself.” Jesus’ active obedience is perfect. In human flesh, as a representative of our race, He perfectly loved His neighbor. He thought rightly, spoke rightly, acted in love. He healed the sick and forgave sins. And everything He did, He did out of perfect love to God. “Love the LORD your God with all your heart, soul, and mind.” (Deuteronomy 6:4) the Law commands. And Christ did it. “You must be perfect as your Father in heaven is perfect.” Jesus is perfect in His active obedience.

Jesus’ perfect active obedience assures that His perfect passive obedience suffices to take our sins away and relieve us of the curse of the Law. Jesus’ active obedience is that as a man, he fulfilled the requirements of the Law. Jesus’ passive obedience is that He suffered the just punishment of sins against all mankind. And because Christ is true God, His obedience is sufficient to be credited to all mankind, as St. Paul wrote in Romans 5, “For if, because of one man’s trespass, death reigned through that one man, much more will those who receive the abundance of grace and the free gift of righteousness reign in life through the one man Jesus Christ. … For as by one man’s disobedience the many were made sinners, so by the one man’s obedience the many will be made righteous.” (Romans 5:17, 19)

Christ was born under the Law to redeem us who were under the Law. Redeem means to buy back. Christ earned our salvation in human flesh. He worked slave labor and won freedom for us all. This was not an absolute emancipation done apart from justice, God just declaring us free without paying our debt. No. Christ paid our debt. He earned our salvation. This is why He became a man. And because He is not only born of a woman, but remains forever true God, the price He paid for our sins is inexhaustible, so that St. Paul even says, “Where sin increased, grace abounded all the more.” (Romans 5:20)

Christ was born under the Law in the fulness of time. Yet, until that fulness of time comes to us through faith, we remain slaves under the Law, even though we rightly can be called sons and heirs. Apart from faith in Christ, there is no salvation. So, the appointed time set by our Father when we are freed from the guardianship and management of the Law, is when God sends us His Holy Spirit, so that we receive Christ through faith. We cannot redeem ourselves by our own works. We can only receive this redemption through faith. Yet, until we receive the Spirit of God, we are stuck under the bondage of the Law.

This is why St. Paul wrote this letter. His dear Galatian Christians had been deceived by works-righteous Judaizers, who taught that one had to be justified by works of the Law in order to be a Christian. But it is the Law which imprisons us (Gal. 3:22)! So, St. Paul presses his straying Christians, “Let me ask you only this: Did you receive the Spirit by works of the Law or by hearing with faith? Are you so foolish? Having begun by the Spirit, are you now being perfected by the flesh? … Does He who supplies the Spirit to you and works miracles among you do so by works of the law, or by hearing with faith—just as Abraham ‘Believed God, and it was counted to him as righteousness’?” (Galatians 3:2-3, 4b-6) And so, to those who have received adoption as sons, “God has sent the Spirit of His Son,” the very Holy Spirit, “into our hearts, crying, ‘Abba! Father!’ So,” he concludes, “You are no longer a slave but a son, and if a son, then an heir through God.”

We receive adoption as children of God, when the Holy Spirit grants us faith in the Gospel, which comes through the Word of Christ. Adoption as God’s children is a free gift received through faith alone. This gift is given by the Holy Spirit, who works through the Word, through the Gospel and Sacraments. This is why St. Paul wrote in Galatians 3, “For in Christ Jesus you are all sons of God, through faith. For as many of you as were baptized into Christ have put on Christ.” (vss. 26-27)

And so, your works of the Law have nothing to do with your inheritance. They have nothing to do with you becoming a child of God, as even St. James writes in his epistle, “Of His own will He brought us forth by the Word of Truth,” (1:18). So, no sin or failure ought make you doubt your status in God’s family and the inheritance which Christ has won for you. If you focus on your works, then you will always be in doubt. But if you focus on Christ’s redemption, your salvation can never be in doubt. And Christ’s redemption is only given to you by the Holy Spirit through the Word of Christ.

And so, the celebration of Christmas is not only that God became a man, but that we have been born of God! Jesus’ birth in the manger is not some humanist message of peace and love, putting aside our differences to enjoy family time and to recognize the goodness of humanity. No, Jesus’ birth in the manger is about the redemption of humanity, so that we humans may call ourselves God’s children. Jesus became a man, born of a woman, born under the Law, to save us from the curse of the Law, to redeem us from our sins.

And so, we no longer live under the strictures of the elementary principles of this world, but rather we walk by the Spirit, who guides our hearts to do God’s will. We do not seek to look good on the outside, but we desire to be good. And so, to battle our sinful impulses, we turn to Christ for strength and forgiveness. We use the law as our tool when we need it, but we do not trust in it. The Law makes slaves. But through faith in Christ Jesus, we are not slaves. We are sons, heirs, children of God who are pleasing to Him for Christ’s sake. And Christ’s redemption will always be sufficient for us to call ourselves God’s children. We are God’s children now. And at the right time, we will see Him as He is, for we will be like Him. Amen.  

From the bondage that oppressed us,

From sin’s fetters that possessed us,

From the grief that sore distressed us,

We, the captives, now are free. Amen

(Come, Your Hearts and Voices Raising, P. Gerhardt, LSB 375:4)