It might seem reasonable at first to simply assume that Paul is saying that the Law was added in response to sin, to curb sin, and to increase holiness through law keeping. But, nearly to the contrary, it is more likely that Paul means that it was added to (1) expose sin—to make it known, (2) to objectify the legal condemnation of sin, and (3) to increase sin itself, thus showing the wicked, fallen, hopeless state of mankind.
The law was […] offered to fallen man in order that, lacking all faculty of fulfilling the law, he may fulfill it through Christ.
Therefore, the promulgation of the law to Israel on Mount Sinai was a very gracious act. (Johannes Wollebius, Compendium Theologiae Christinae, p. 76)
Throughout this series we have been answering the question from which we began, “how was Christ administered to the saints of the Old Testament?” We have shown that Christ was administered and dispensed by means of the Land and Seed promises, the ordained Sacrifices, the Sacrament of Circumcision, and we have for the last couple of posts been discussing the Law itself as part of the administration and dispensation of the one redemptive work of Christ to the saints of the Old Testament.
Contrary to the assumption of many, the Law was not simply a ministration of death (2 Cor. 3:7), that which slew Paul (Rom. 7:9), the sting of death (1 Cor. 15:56), etc., but was rather a very gracious act of God—a redeeming act of God—Christ Himself promulgating the Law to His own people from Mt. Sinai, carrying them on eagle’s wings through the Wilderness, and in the Law displaying His own perfect and most desirable character. As we discussed last time, the Law became death to apostate Jews, not because it was not holy, righteous, and good in itself, but because we are fallen and evil by nature. What the Jews had failed to see was the purpose of the Law, preferring in the pride of their uncircumcised hearts to “do this and live,” rather than believe in their hearts and confess with their mouths the faith that was by it brought near.
So, what was the true purpose of the Law? Why did Christ the King in His everlasting love and kindness give that which was found to be death to many, especially when there were so many abundant promises given to the Jews in the Old Testament?
In Galatians 3, having just successfully proven that “the inheritance is not of the Law”—the promise having always been in Christ, Paul goes on to ask the very question at hand:
What purpose then does the law serve? (Gal. 3:19)
If the Law was merely added to the promise given to Christ (vv. 15-17), in no wise contradicting it (v. 21), and was never the means for conveying the promise anyhow, then why was it ever given in the first place? What was its purpose and intention?
Paul begins his answer,
It was added because of transgressions. (v. 19)
A few senses of this phrase seem to be allowable in the text, each finding warrant in parallel passages in Paul’s corpus. It might seem reasonable at first to simply assume that Paul is saying that the Law was added in response to sin, to curb sin, and to increase holiness through law keeping. But, nearly to the contrary, it is more likely that Paul means that it was added to (1) expose sin—to make it known, (2) to objectify the legal condemnation of sin, and (3) to increase sin itself, thus showing the wicked, fallen, hopeless state of mankind. Each of these senses are explicitly represented in the following passages from Romans, and each in quite similar contexts as the Galatians passage above:
[T]he law brings about wrath; for where there is no law there is no transgression. (Rom. 4:15)
For until the law sin was in the world, but sin is not imputed when there is no law. (Rom. 5:13)
[T]he law entered that the offense might abound. (Rom. 5:20)
Is the law sin? Certainly not! On the contrary, I would not have known sin except through the law. (Rom. 7:7)
[S]in, taking opportunity by the commandment, produced in me all manner of evil desire. For apart from the law sin was dead. (Rom. 7:8)
Has then what is good [the Law] become death to me? Certainly not! But sin, that it might appear sin, was producing death in me through what is good, so that sin through the commandment might become exceedingly sinful. (Rom 7:13)
All of these passages come to much the same point, summarized by Paul in Romans 3:19-20:
Now we know that whatever the law says, it says to those who are under the law, that every mouth may be stopped, and all the world may become guilty before God. Therefore by the deeds of the law no flesh will be justified in His sight, for by the law is the knowledge of sin.
The Law was added because of transgressions, to make them known, to make them legal transgressions, to make them abound, and even to stir them up through the concupiscence of men’s hearts. And all to what end? To shut the mouth of the whole world, making public and known each and every man’s stone-cold guilt before God.