Few questions in Christian theology have generated as much confusion as the relationship between the law and the gospel. Is the law abolished? Is it still binding? Did Jesus come to destroy the law or to fulfill it? How does grace relate to God’s commandments? These questions are not merely academic. They touch the daily life of every believer. How one answers them shapes the reading of Scripture, the understanding of salvation, and the living of the faith.
In Galatians 3:15–29, the apostle Paul addresses these questions with surgical precision. Having already demonstrated that justification comes by faith and not by works of the law (Galatians 3:1–14), Paul now anticipates a natural objection: if the law does not justify, then why did God give it in the first place? Was the law a mistake? Did the Mosaic covenant contradict the Abrahamic promise? Paul’s answer is a masterpiece of theological reasoning.
The Priority of the Promise
Paul begins with an analogy drawn from everyday legal practice:
“To give a human example, brothers: even with a man-made covenant, no one annuls it or adds to it once it has been ratified.” (Galatians 3:15, ESV)
The principle is straightforward. Once a covenant (or contract, or will) has been legally ratified, it cannot be altered or set aside by a later arrangement. Paul then applies this principle to God’s dealings with Abraham: “Now the promises were made to Abraham and to his offspring” (Galatians 3:16). The Abrahamic covenant, with its promise of blessing through faith, was ratified by God Himself. It is unalterable.
Here is the crucial point. The Mosaic Law came 430 years after the Abrahamic promise (Galatians 3:17). Since the promise was already ratified, the law could not annul it, modify it, or replace it. The law did not introduce a new way of being right with God. The way of faith established with Abraham remained in force. This is not a minor chronological observation. It is a fundamental theological argument. The promise has priority over the law, both in time and in substance.
Then Why the Law?
This naturally raises the question that Paul himself voices: “Why then the law?” (Galatians 3:19). If the promise was already sufficient, why did God add the law at Sinai? Paul gives a direct answer:
“It was added because of transgressions, until the offspring should come to whom the promise had been made.” (Galatians 3:19, ESV)
The law was added “because of transgressions.” This phrase can be understood in at least two complementary ways. First, the law was given to define and expose sin. Before the law, sin existed, but it was not clearly identified and categorized. The law drew sharp lines. It named specific sins. It made transgression visible and unmistakable. Paul says something similar in Romans 3:20: “Through the law comes knowledge of sin.” The law functions as a diagnostic tool. It does not cause the disease, but it reveals it with painful clarity.
Second, the law was given to restrain sin. By establishing clear boundaries and attaching consequences to their violation, the law served as a restraint on human wickedness. It did not eliminate sin from the human heart, but it set limits on its expression and provided a framework for civil and religious life in Israel.
Notice also that the law was temporary in its function. It was added “until the offspring should come.” The law had an expiration date built into its very purpose. It was never intended to be the permanent arrangement between God and His people. It was a provisional measure, designed to serve a specific role in the unfolding story of redemption, until Christ (the promised offspring) arrived.
Is the Law Opposed to the Promises?
Paul anticipates yet another objection. If the law was temporary and limited in its purpose, does that mean it stands in opposition to God’s promises? His answer is emphatic:
“Is the law then contrary to the promises of God? Certainly not!” (Galatians 3:21, ESV)
The law and the promise are not enemies. They serve different functions within the same divine plan. The promise offers life through faith. The law was never designed to offer life in the same way. Paul explains: “For if a law had been given that could give life, then righteousness would indeed be by the law” (Galatians 3:21). The law cannot give life because human beings cannot keep it perfectly. The problem is not with the law itself; the problem is with human sin. The law is holy and good (cf. Romans 7:12), but fallen humanity cannot meet its demands.
Instead of giving life, the law does something different: “But the Scripture imprisoned everything under sin, so that the promise by faith in Jesus Christ might be given to those who believe” (Galatians 3:22). The law shuts every mouth and locks every door except one: the door of faith. By demonstrating that no one can achieve righteousness through obedience, the law drives sinners to the promise. It compels them to look beyond themselves for a righteousness they cannot produce on their own.
The Law as Guardian
Paul then introduces one of his most memorable metaphors:
“So then, the law was our guardian until Christ came, in order that we might be justified by faith.” (Galatians 3:24, ESV)
The word translated “guardian” is the Greek word paidagogos. In the ancient world, a paidagogos was not a teacher in the modern sense. He was a household slave assigned to supervise a child, escorting the child to school, enforcing discipline, and ensuring proper behavior. The paidagogos had real authority over the child, but that authority was always temporary. Once the child reached maturity, the guardian’s role ended.
Paul’s analogy is brilliant. The law functioned like a paidagogos for the people of God. It supervised, restrained, disciplined, and guided. It kept the people of God in line until the appointed time. But it was never the final word. Its entire purpose was to lead God’s people to Christ. Once Christ arrived, the guardian’s role was fulfilled.
“But now that faith has come, we are no longer under a guardian” (Galatians 3:25). This does not mean the law is worthless or that its moral principles are irrelevant. It means that the law’s supervisory role over the people of God has been fulfilled in Christ. Believers are no longer under the law as a system of justification or as a means of maintaining standing before God. They are in Christ, and that changes everything.
Children of God Through Faith
The climax of Paul’s argument is a declaration of breathtaking scope:
“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. There is neither Jew nor Greek, there is neither slave nor free, there is no male and female, for you are all one in Christ Jesus.” (Galatians 3:26–28, ESV)
Under the law, there were distinctions: Jew and Gentile, clean and unclean, insider and outsider. In Christ, those distinctions no longer determine standing before God. Every believer, regardless of ethnic background, social status, or gender, is a full son of God through faith. The word “son” here carries legal weight. In the Roman world, a son was an heir with full rights. Paul is declaring that every believer, without exception, has the full status of an heir in God’s family.
This was revolutionary in the first century, and it remains revolutionary today. The gospel does not merely tolerate diversity within the people of God. It creates a new unity that transcends the deepest divisions of human society. This is not achieved by erasing differences but by placing all believers on the same footing before God: justified by faith, united in Christ, heirs of the promise.
Heirs According to Promise
Paul closes this section by tying everything back to Abraham:
“And if you are Christ’s, then you are Abraham’s offspring, heirs according to promise.” (Galatians 3:29, ESV)
The argument comes full circle. The promise was made to Abraham and to his offspring. Christ is the true offspring. And all who belong to Christ are, by virtue of that union, Abraham’s offspring and heirs of the promise. The law did not replace the promise. It served the promise. It guarded, guided, and governed God’s people until the promise was fulfilled in Christ. Now that Christ has come, the people of God live by faith in Him, not under the supervision of the law.
Implications for the Church Today
The relationship between law and gospel is not an abstract puzzle for theologians. It is a daily reality for every Christian. When believers struggle with guilt, they need to know whether standing before God depends on personal performance or on Christ’s finished work. When moral decisions arise, believers need to know whether the law guides or condemns. When fellow Christians from different backgrounds are encountered, what unites them must be understood.
Paul’s teaching in Galatians 3 gives clear answers. The law reveals sin. The gospel provides the remedy. The law cannot justify. Faith in Christ does. The law was a temporary guardian. Christ is the permanent Savior. The law divides humanity into categories. The gospel unites all believers as one in Christ.
This is not antinomianism, the rejection of all moral law. Paul is not arguing that God’s moral standards are irrelevant. He is arguing that the law, as a covenant system through which one gains or maintains right standing before God, has been superseded by something far greater: the promise fulfilled in Jesus Christ. The believer now lives not under the compulsion of the law but in the freedom of the Spirit, guided by the same moral character of God that the law reflected, but empowered by grace rather than burdened by condemnation.
The law pointed to Christ. Christ has come. And in Him, every believer stands as a son, an heir, and a recipient of the promise made to Abraham so long ago.
Rooted. Reasoned. Relevant.
