Commentary - Galatians 3:19-22

Bird's-eye view

In this dense section of Galatians, Paul is answering a crucial question that his entire argument has provoked. If salvation and righteousness are by faith in the promise made to Abraham, and not by works of the law, then what was the point of the law in the first place? "Why the Law then?" he asks. It is a fair question, and one he answers with surgical precision. The law was not a mistake, nor was it Plan B. It had a specific, temporary, and divinely ordained purpose.

Paul explains that the law was added as a temporary measure to deal with transgressions. It was a parenthesis, inserted between the promise to Abraham and the fulfillment of that promise in Christ, the Seed. Its function was to corral sin, to define it, and to show its utter sinfulness, effectively driving us to the only possible solution: the promise of God received by faith. The law was never intended to give life; if it could have, righteousness would have come through it. Instead, its purpose was to act as a jailer, shutting everyone up under sin, so that the release offered by faith in Jesus Christ would be understood as the only way out. The law, therefore, does not oppose the promises but serves them, albeit in a severe and preparatory way.

Outline

Context In Galatians

Paul has spent the bulk of chapter 3 arguing that justification is by faith alone, using Abraham as the premier example. The promise given to Abraham predated the Mosaic Law by 430 years, and the giving of the law did not and could not annul that foundational promise. The inheritance comes through promise, not law. This line of reasoning naturally leads to the question Paul anticipates and addresses here: "Why the Law then?" The Judaizers troubling the Galatian churches were elevating the law to a place it was never meant to occupy, making it a condition for righteousness. Paul's task here is to put the law back in its proper, subordinate, and temporary place, showing how it functions in service to the gospel, not in opposition to it.

Key Issues

Verse by Verse Commentary

v. 19 Why the Law then? It was added because of trespasses, having been ordained through angels by the hand of a mediator, until the seed would come to whom the promise had been made.

Paul asks the obvious question on behalf of his opponents. If the promise is everything, what's the law for? His answer is that it was "added because of trespasses." The Greek word is parabasis, which means a stepping across a line. The law was given to turn sin into transgression. Sin was already in the world, but the law came in to draw a clear line in the sand, to define sin with specificity, and in so doing, to increase the transgressions. It was not given to make men righteous, but to show them how unrighteous they were. It was given to make the problem worse, in a sense, so that the need for a cure would be felt acutely. This is what Paul argues in Romans as well; the law came in so that the trespass might abound (Rom. 5:20).

He then notes the way it was delivered: "ordained through angels by the hand of a mediator." This refers to the giving of the law at Sinai, with Moses as the mediator between God and Israel. Paul's point here is to show the indirectness of the law's administration compared to the directness of the promise. The promise was given by God directly to Abraham. The law was a more complex affair, involving angels and a human go-between. This is not to denigrate the law, but to place it in its proper context. It was glorious, but it was a lesser glory.

And crucially, it was temporary. It was put in place "until the seed would come." The law had an expiration date. That seed, as Paul has already established, is Christ (Gal. 3:16). The law was the tutor, the babysitter, the guardian, until the heir came of age. Once Christ came, the law's function as a temporary guardian was fulfilled.

v. 20 Now a mediator is not for one person only, whereas God is one.

This is a notoriously difficult verse, but in the context of Paul's argument, the meaning becomes clearer. A mediator, by definition, implies at least two parties. Moses mediated between God and Israel. But when God made His promise to Abraham, He acted alone. He swore by Himself. The covenant with Abraham was unilateral. Paul's point is that the promise is superior because it rests on the unchanging character of the one God. "God is one." The law involved a negotiation, a bilateral covenant with stipulations for two parties. The promise, however, is a straightforward declaration from the one true God. It is therefore more stable, more certain. The law is conditional; the promise is absolute.

v. 21 Is the Law then contrary to the promises of God? May it never be! For if a law had been given which was able to impart life, then righteousness would indeed be by law.

Paul anticipates another objection. If the law and the promise are so different, are they opposed to one another? He answers with his characteristic "May it never be!" (mē genoito). They are not enemies; they have different jobs. The law's job was never to give life. If there were a law that could do that, then God would have given it, and righteousness would be a matter of law-keeping. But no such law exists, because fallen man is incapable of keeping it perfectly.

The law makes demands, but it provides no power to meet those demands. It tells you what to do, but gives you no ability to do it. It is like telling a man with no legs to run a marathon. The instructions might be excellent, but they are useless for imparting the ability to run. The law diagnoses the disease; it does not provide the cure. The promise, on the other hand, is all about God giving life where there was death.

v. 22 But the Scripture has shut up everyone under sin, so that the promise by faith in Jesus Christ might be given to those who believe.

Here is the summation of the law's purpose. The Scripture, referring to the Old Testament law, has "shut up everyone under sin." The Greek word for "shut up" (sugkleió) means to enclose, to lock in, like fish in a net or prisoners in a jail. The law acts as a jailer. It corrals all of humanity, Jew and Gentile alike, into one prison cell called "sin." It leaves no room for escape, no possibility of parole through good behavior. It pronounces everyone guilty.

But this imprisonment is not for damnation's sake alone. It has a glorious, redemptive purpose. It is "so that the promise by faith in Jesus Christ might be given to those who believe." The law locks every other door so that the one door of faith becomes the only way out. It strips us of all self-righteousness and all hope in our own performance so that we are driven to despair of ourselves and to cast ourselves entirely upon the mercy of God offered in Christ. The law wounds, so that the gospel can heal. It condemns, so that grace can save. It shuts us up, so that Christ can set us free.

Key Words

Parábasis, "Transgression"

Parábasis is not simply sin in general (hamartia), but a specific kind of sin: the violation of a known law. It means to step over a line that has been clearly drawn. Paul's point is that the Mosaic Law was given to make sin manifest as transgression. It took the general sinfulness of humanity and codified it, making the guilt of man explicit and undeniable.

Mesítēs, "Mediator"

A mesítēs is a go-between, an intermediary who stands between two parties to broker an agreement. Moses was the mediator of the Old Covenant at Sinai. Paul contrasts this with the promise made to Abraham, which was given directly by God without an intermediary, highlighting the superiority and directness of the promise. Christ, of course, is the mediator of a new and better covenant, but He is not a mere go-between. He is Himself God, one of the parties, representing us to Himself.

Application

The practical application of this passage is immense. First, it teaches us the right way to view the Old Testament law. It is not a ladder to climb up to God. It is a mirror that shows us our filth and our desperate need for a savior. Any attempt to use the law as a means of justification is to misuse it and to fall from grace, which was the central problem in Galatia. The law is good, but only if used lawfully, and its lawful use is to drive us to Christ.

Second, this passage demolishes all forms of self-righteousness. The Scripture has shut up everyone under sin. There are no exceptions. This is the great equalizer. No one can stand before God and plead their own case based on their performance. We are all in the same prison, and we all need the same savior. This truth should produce humility in us and a profound gratitude for the grace of God.

Finally, it magnifies the glory of the promise. The promise is not a reward for the worthy, but a gift for the guilty. It is received by faith alone, which is simply the empty hand that receives the gift. The law shows us our bankruptcy; the gospel offers us the free riches of Christ. Our response should be to abandon all trust in our own efforts and to believe, to rest wholly in the finished work of Jesus Christ, the promised Seed.