I've recently enjoyed and appreciated a less familiar portion of Luther's lectures on Galatians, in which he comments at length on St. Paul's discussion of Hagar and Sarah (Galatians 4:21-27). Especially in view of recent events in my own life, and in light of recent synodical happenings, I find Luther's catechesis on this Word of the Lord to be timely and poignant, encouraging and comforting. It's a longer passage, true, and Luther can go on a bit on certain points, but his proclamation of the Gospel under the weight and burden of the Cross is worth it:
"The Jerusalem that is above, that is, the heavenly Jerusalem, is the church here in time. It is not, by anagoge, our fatherland in the life to come or the church triumphant, as the idle and unlettered monks and scholastic doctors imagined. Paul says (Galatians 4:26) that the old, earthly Jerusalem pertains to Hagar; that she is in slavery with her children; that she has been abolished; and that a new and heavenly Jerusalem, which is lordly and free, has been divinely established, not in heaven but on earth, to be the mother of us all, of whom we have been born and are being born every day. Therefore it is necessary that this mother of ours, like the birth she gives, be on earth among men; yet she gives birth in the Spirit, by the Ministry of the Word and of the Sacraments, not physically.
"I say this to keep us from being led astray by our thoughts into heaven. We should know that Paul is contrasting the Jerusalem that is above with the earthly Jerusalem, not spatially but spiritually. Spiritual things are distinct from physical or earthly things. Spiritual things are ‘above’; earthly things are ‘below.’ Thus the Jerusalem that is above is distinguished from the physical and temporal Jerusalem that is below, as I have said, not spatially but spiritually. For the spiritual Jerusalem, which began in the physical Jerusalem, has no prescribed location, as the one in Judea does; but it is scattered throughout the world and can be in Babylonia, Turkey, Tartary, Scythia, India, Italy, or Germany, on the islands of the sea, on mountains, in valleys, and everywhere in the world where there are men who have the Gospel and believe in Christ.
"Therefore Sarah, or Jerusalem, our free mother, is the church, the bride of Christ who gives birth to all. She goes on giving birth to children without interruption until the end of the world, as long as she exercises the Ministry of the Word, that is, as long as she preaches and propagates the Gospel; for this is what it means for her to give birth. Now she teaches the Gospel in such a way that we are set free from the curse of the Law, from sin, death, and other evils, not through the Law and works but through Christ. Therefore the Jerusalem that is above, that is, the church, is not subject to the Law and works; but she is free and is a mother without Law, sin, or death. And as the mother is, so are the children to whom she gives birth.
"Therefore this allegory teaches in a beautiful way that the church should not do anything but preach the Gospel correctly and purely and thus give birth to children. In this way we are all fathers and children to one another, for we are born of one another. I was born of others through the Gospel, and now I am a father to still others, who will be fathers to still others; and so this giving birth will endure until the end of the world. But I am speaking, not about Hagar’s giving birth, who gives birth to slaves through the Law, but about free Sarah’s, who gives birth to heirs without the Law, without works or their own efforts. That Isaac is the heir and Ishmael is not, even though both are genuine sons of Abraham, takes place through the Word of promise, specifically: ‘Sarah your wife shall bear you a son, and you shall call his name Isaac’ (Gen. 17:19). Sarah understood this very well, and therefore she said: ‘Cast out this slave woman with her son’ (Gen. 21:10). Therefore just as Isaac has the inheritance from his father solely on the basis of the promise and of his birth, without the Law or works, so we are born as heirs by Sarah, the free woman, that is, by the church. She teaches, cherishes, and carries us in her womb, her bosom, and her arms; she shapes and perfects us to the form of Christ, until we grow into perfect manhood (Eph. 4:13). Thus everything happens through the Ministry of the Word. It is the duty of the free woman to go on giving birth to children endlessly, that is, to sons who know that they are justified by faith, not by the Law.
"‘For it is written: Rejoice, O barren one that does not bear; break forth and shout, thou who art not in travail; for the desolate hath more children than she who hath a husband’ (Galatians 4:27). Paul quotes this passage, which is completely allegorical, from the Prophet Isaiah. It is written, he says, that the mother of many children, who has a husband, must grow sick and perish, while the barren one, who does not bear, must have very many children. Hannah sings the same way in her canticle, from which Isaiah took this prophecy: ‘The bows of the mighty are broken, but the feeble gird on strength. Those who were full have hired themselves out for bread, but those who were hungry have ceased to hunger. The barren has borne seven, but she who has many children is forlorn’ (1 Samuel 2:4–5). It is an amazing thing, she says: the one who was prolific will be barren, and the one who was barren will be prolific. Those who were mighty, satisfied, alive, righteous, blessed, rich, and glorious will be feeble, hungry, sentenced to death, sinful, condemned, poor, and shameful; and, on the other hand, the feeble and the hungry will be mighty and satisfied.
"With this allegory from the Prophet Isaiah, Paul shows the difference between Hagar and Sarah, that is, between the synagogue and the church, or between the Law and the Gospel. It is as though he were saying: ‘The Law, the husband of a prolific woman, that is, of the synagogue, gives birth to very many children.’ For men of every age, not only the ignorant but those who are the wisest and best — in other words, the whole human race with the exception of the children of the free woman — do not see or recognize any other righteousness, nor to say any more excellent righteousness, than that of the Law. (Now under the term ‘Law’ I am including all laws, both human and divine.) Therefore if they follow the Law and perform its outward works, they think they are righteous. All such men are slaves, not free men, because they are sons of Hagar, who gives birth into slavery. If they are slaves, they do not share in the inheritance but are cast out of the house. ‘The slaves do not continue in the house forever’ (John 8:35); in fact, they have now been thrown out of the kingdom of grace and freedom. ‘He who does not believe is condemned already’ (John 3:18). Therefore they remain under the curse of the Law, under sin, death, and the power of the devil, under the wrath and judgment of God.
"Now if even the Moral Law of God, the Decalogue, gives birth only to slaves — that is, does not justify but only terrifies, accuses, condemns, and brings consciences to the point of despair — how, I ask you, could the laws of the pope or human tradition justify? Therefore anyone who teaches or urges either the Law of God or human traditions as something necessary for righteousness in the sight of God does nothing other than give birth to slaves. And yet such theologians are regarded as the best; they earn the applause of the world and are the most prolific mothers, that is, have an infinite number of disciples. Since reason does not understand what faith and true godliness are, it neglects and despises them. Naturally, it is impressed by superstition and hypocrisy, that is, by the righteousness of works, which is so brilliant and successful that it is the mighty empress of the universe. Therefore those who teach the righteousness of works on the basis of the Law give birth to many sons, but all of these are slaves who will be thrown out of the house and condemned.
"Sarah, the free woman, on the other hand, that is, the true church, seems to be barren; for the Gospel, the Word of the cross, which the church preaches, is not as brilliant as is the teaching about the Law and works, and therefore it has few pupils who cling to it. Besides, it has the reputation of forbidding good works, making men idle and faint, stirring up heresies and sedition, and being the cause of every evil. Therefore it does not seem to have any success or prosperity; but everything seems to be filled with barrenness, waste, and despair. Hence the wicked are fully persuaded that the church will soon perish along with its doctrine. The Jews were altogether sure that the church established by the Apostles would soon be deserted. To it they gave the hateful name ‘sect’; for so they spoke to Paul: ‘With regard to this sect we know that everywhere it is spoken against’ (Acts 28:22). Similarly today, how often, I ask you, have our opponents rejoiced in a false hope that we would surely be crushed at this or that time? Christ and the Apostles were crushed; but when they were dead, the teaching of the Gospel was spread more widely than when they were alive. Thus our opponents can crush us, but ‘the Word of the Lord will abide forever’ (1 Peter 1:25). Regardless of how barren and deserted the church of Christ seems, therefore, or of how much it is said to teach heretical and seditious doctrine, it alone gives birth to children and heirs, through the Ministry of the Word.
"Therefore the Prophet grants that the church is engaged in a conflict; otherwise he would not urge her to rejoice. He grants that in the eyes of the world she is barren; otherwise he would not call her a barren and desolate one that does not bear. But he says that she is prolific in the eyes of God. Therefore he tells her to rejoice. It is as though he were to say: ‘Desolate and barren, you do not have the Law as your husband; therefore you do not have children either. But rejoice. For even though you are deprived of the husband Law, like a virgin of marriageable age who has been deserted (he does not want to call her a widow), who would have a husband if he had not deserted her or had not been killed — you, I say, who are desolate and deserted by the husband Law and are not subject to marriage with the Law, will be the mother of an infinite number of children.’ Therefore the church of the new covenant is completely without Law so far as her conscience is concerned. In the eyes of the world, therefore, she seems to be deserted. But even though she appears barren, without Law or works, yet in the eyes of God she is very prolific, giving birth to an endless number of children, and free ones at that. How? Not through the husband Law but through the Word and the Spirit of Christ, given through the Gospel, she conceives, bears, and rears her children.
"With this allegory, then, Paul shows the distinction between the Law and the Gospel very clearly: first, when he calls Hagar the old covenant and Sarah the new; next, when he calls the former a slave and the latter a free woman; finally, when he says that the one who has a husband and is prolific will grow ill and will be cast out of the house with her children, but that the one who is barren and desolate will become prolific and will produce an infinite number of children, all of whom will be heirs. These are the essential differences between the people of faith and the people of the Law. The people of faith does not have the Law as its husband; it is not in slavery; it was not born of the present Jerusalem as its mother. But it has the promise; it is free; and it is born of Sarah, the free woman.
"Therefore Paul separates the spiritual people of the new covenant from the Law when he says that this people is not the child of Hagar, who had a husband, but of Sarah, the free woman, who does not know the Law. In this way he sets the people of faith far above and beyond the Law. But if it is above and beyond the Law, then it is justified, not by the Law and works but solely by its spiritual birth, that is, by faith. For spiritual birth is nothing other than faith. Now just as the people of grace neither has the Law nor can have it, so the people of the Law neither has grace nor can have it; for it is impossible for Law and grace to exist together. Either we must be justified by faith and lose the righteousness of the Law, or we must be justified by the Law and lose grace and the righteousness of faith. It is a bitter and tragic loss when we keep the Law and lose grace. On the other hand, it is a fortunate and saving loss when we keep grace and lose the Law.
"Seeing that Paul sets this forth with the greatest care, we are very careful to show the difference between the Law and the Gospel clearly. This is very easy so far as the words themselves are concerned. For who does not see that Hagar is not Sarah and that Sarah is not Hagar, or that Ishmael neither is nor has what Isaac is and has? This can be determined easily. But in profound terrors and in the agony of death, when the conscience struggles with the judgment of God, to be able to say with firm confidence: ‘The Law does not apply to me at all, because my mother is Sarah, who gives birth, not to salves but to free children and heirs’ — that is the most difficult thing there is.
"With this quotation from Isaiah, Paul proved that Sarah is the true mother, who gives birth to free children and heirs; and, on the other hand, that Hagar does indeed give birth to many children, but that they are slaves, who must be cast out of the house. Besides, since this passage speaks about the abrogation of the Law and about Christian liberty, it must be considered carefully. For just as it is our highest and most important doctrine to know that we are justified and saved through Christ, so, by antithesis, it is very important to have the correct understanding of the abrogation of the Law. The knowledge that the Law has been abrogated is of great value for confirming our teaching about faith and for providing a sure comfort for consciences, especially in their deep anxiety.
"This passage in Isaiah about the free mother who gives birth to free children teaches that for those who believe in Christ the entire Law, with all its terrors and troubles, has been abrogated. Therefore it is a truly outstanding and comforting passage, urging that the barren and desolate one rejoice, even though, according to the Law, she should rather be ridiculed or pitied. For according to the law barren women were accursed. But the Holy Spirit reverses this sentence and pronounces the barren one praiseworthy and blessed, but the prolific one who has children He pronounces accursed. Regardless of how desolate and barren Sarah, that is, the church, may appear to be in the eyes of the world because she does not have Law and works, she is, according to the testimony of the Prophet, the prolific mother of an infinite number of children in the eyes of God. By contrast, regardless of how great and abundant the fertility and bearing may be under Hagar, there are no children left; for the children of the slave woman are cast out of the house together with their mother, and they do not receive the inheritance with the children of the free woman, as Paul says further on (Galatians 4:30).
"Since, therefore, we are children of the free woman, the Law, our old husband (Rom. 7:1–6), has been abolished; as long as it had dominion over us, it was impossible for us to give birth in the Spirit to children who knew grace, but they remained slaves. When the Law has dominion, men are not idle. They work hard, and they bear the burden of the day and the scorching heat (Matt. 20:12). They bear and give birth to many children, but both the parents and the children are illegitimate and do not belong to a free mother. Therefore they are eventually cast out of the inheritance with Ishmael; they die and are damned. Hence it is impossible for men to be justified and saved through the Law. There is, of course, much labor and birth in the Law; but none of this grants the inheritance. Therefore the Law, with all its children, must be cast out; that is, cursed be any doctrine, life, or religion that strives to achieve righteousness in the sight of God by means of the Law or works.
"When Thomas Aquinas and other scholastics speak about the abrogation of the Law, they say that after Christ the civil and ceremonial laws are fatal, and that therefore they have now been abrogated, but not the moral laws. These men do not know what they are saying. When you want to speak about the abrogation of the Law, discuss chiefly the law in the proper sense of the word — the Law in the spiritual sense. Include the entire Law, without distinguishing between the civil, the ceremonial, and the moral. For when Paul says that through Christ we have been set free from the curse of the Law (Gal. 3:13), he is certainly speaking about the entire Law, and especially about the Moral Law. It alone actually accuses, curses, and condemns consciences; but the other two kinds do not. Therefore we say that the Law of the Decalogue has no right to accuse and terrify the conscience in which Christ reigns through grace, for Christ has made this right obsolete.
"This does not mean that the conscience does not feel the terrors of the Law at all. Of course it feels them. But it means that the conscience cannot be condemned and brought to the point of despair by such things. For ‘there is now no condemnation for those who are in Christ Jesus’ (Rom. 8:1); again: ‘If the Son makes you free, you will be free indeed’ (John 8:36). Regardless of how terrified the Christian is by the Law and how much he acknowledges his sin, he does not despair; for he believes in Christ, into whom he has been baptized and through whom he has the forgiveness of sins. Now if our sin has been forgiven through Christ Himself, the Lord of the Law — and forgiven by His having given Himself for it — the Law, that slave, no longer has a right to accuse and condemn us because of our sin; for this has been forgiven, and we have become free by the deliverance of the Son. Therefore the entire Law has been abrogated for believers in Christ.
"‘But I have not done anything good and am not doing anything now!’ Here you neither can nor must do anything. Merely listen to this joyful message, which the Spirit is bringing to you through the Prophet: ‘Rejoice, O barren one that dost not bear!’ It is as though He were saying: ‘Why are you so sorrowful when you have no reason to be sorrowful?’ ‘But I am barren and desolate.’ ‘Regardless of how much you are that way, since you have no righteousness on the basis of Law, Christ is still your Righteousness. He became a curse for you; He has redeemed you from the curse of the Law (Gal. 3:13). If you believe in Him, the Law is dead for you. As much as Christ is greater than the Law, that much better is the righteousness you have than the righteousness of the Law. Moreover, you are not barren either, because you have more children than she who has a husband.’
"A second kind of abrogation of the Law, an outward one, is that the political laws of Moses do not apply to us at all. Therefore we should not restore them to the courthouse or chain ourselves to them in some superstitious way, as some men who were ignorant of this liberty did several years ago. Nevertheless, although the Gospel does not subject us to the civil laws of Moses, it does not completely set us free from obedience to all political laws; but in this bodily life it subjects us to the laws of the state in which we live, and it commands everyone to obey his magistrate and his laws, ‘not only to avoid God’s wrath but also for the sake of conscience’ (1 Peter 2:13–14; Rom. 13:5). Nor would it be a sin if the emperor used some of the civil laws of Moses; in fact, it would be a good idea if he did. Therefore the sophists are in error when they imagine that after Christ the civil laws of Moses are fatal to us.
"We are not bound by the ceremonies of Moses either, much less by those of the pope. But because this life in the body cannot be completely without ceremonies and rituals, since there must be some sort of discipline, the Gospel permits ordinances to be established in the church regarding festivals, prescribed times, prescribed places, etc., so that the people may know on what day, at what time, and in what place they should gather to hear the Word of God. It permits the appointment of certain lessons, just as in school, especially for the sake of children and uneducated people, so that they can be taught more easily. But it permits such things to be established with the purpose that all things in the church should be done decently and in order (1 Cor. 14:40), not that those who observe such ordinances should merit the forgiveness of sins. Besides, they can be omitted without sinning, so long as this is done without offending the weak. Nor is it true that after Christ has been revealed, the ceremonies of Moses are fatal; otherwise Christians would sin when they observe the festivals of Easter and Pentecost, which the ancient church established on the basis of the example of the Law of Moses, although in a far different manner and for a different purpose.
"But here Paul is speaking principally about the abrogation of the Moral Law, and this should be considered carefully. He is arguing against the righteousness of the Law in order to establish the righteousness of faith, and he concludes: ‘If grace alone or faith in Christ justifies, then the entire Law has been completely abrogated.’ He supports this by the testimony of Isaiah, which invites the barren and desolate church to rejoice. She seems not to have any children of her own or any hope of having children. That is, she does not have disciples and does not receive any applause, because she preaches the Word of the cross about Christ the Crucified, in opposition to all the wisdom of the flesh. ‘But, O barren one,’ says the Prophet, ‘do not let any of this bother or disturb you. Rather exult and rejoice, for the desolate has more children than she who has a husband. That is, the one who has a husband and many children will grow ill. But you, the barren and desolate one, will abound with children.’
"Paul calls the church barren because her children are not born by means of the Law or works or any human efforts of powers but in the Holy Spirit through the Word of faith. This is purely a matter of being born, not of doing any works. Those who are prolific, on the other hand, labor and strain greatly in travail; this is purely a matter of doing works, not of giving birth. But those who try to achieve the status of sons and heirs by the righteousness of the Law or by their own righteousness are slaves, who will never receive the inheritance even though they work themselves to death with their great effort; for they are trying, contrary to the will of God, to achieve by their own works what God wants to grant to believers by sheer grace for Christ’s sake. Believers do good works; but they do not become sons and heirs through this, for this has been granted to them by their birth. Now that they have become sons for Christ’s sake, they glorify God with their good deeds and help their neighbor."
(Luther’s Works, Volume 26, CPH 1963, alt.)