Paul recounts how he publicly confronted Peter in Antioch because Peter’s withdrawal from Gentile believers denied the gospel in practice. This was not a minor issue of table manners. Peter’s actions implied that Gentiles needed to live like Jews to enjoy full fellowship, but Paul insists that justification comes not by works of the law but through faith in Christ, on the basis of Christ’s self-giving death.

Paul begins with a real event in Antioch. Peter had been eating with Gentile believers, which showed that he recognized them as full members of God’s people in Christ. But when certain men associated with James arrived, Peter drew back and separated himself from the Gentiles. The text says he did this because he feared the circumcision group. Paul does not say that James himself approved of this behavior. The point is that Peter changed his conduct out of fear.

This shift was serious because it was both public and influential. Other Jewish believers followed Peter’s example, and even Barnabas was carried along by it. Paul calls this hypocrisy because their conduct no longer matched what they knew to be true from the gospel. Their actions suggested that Gentile believers were not fully acceptable unless they also took on Jewish law-shaped identity markers. For that reason Paul rebuked Peter publicly. Since the sin was public and was leading others astray, the correction also had to be public.

Paul says they were not behaving consistently with the truth of the gospel. That makes clear that the issue was theological, not merely social. Table fellowship was communicating something about who belongs among God’s people. Peter had not necessarily spoken a command that Gentiles must become Jews, but his behavior pressured them in that direction. By withdrawing, he was effectively sending the message that full fellowship required living like Jews.

Paul then states the heart of the matter. Even Jews by birth know that a person is not justified by works of the law, but through faith in Christ. To be justified is to be declared righteous before God. Paul repeats this point several times so there can be no misunderstanding: works of the law cannot be the basis of a right standing before God. In this context, works of the law includes law-defined observances that distinguished Jews from Gentiles, but Paul’s point also extends more broadly. No one will be justified before God by law-keeping.

Paul’s wording holds together two truths that must not be separated. Christ’s faithful, self-giving work is the ground of salvation, and believers receive its benefits by trusting in him. The precise wording has been discussed, but the main meaning is plain: justification comes through Christ rather than through the law. Paul’s account of the Antioch rebuke likely combines his direct words with a compressed summary of the theological point, but that does not change the meaning.

Paul then answers a false conclusion. If, while seeking to be justified in Christ, Jews are found among those counted as sinners, does that make Christ a promoter of sin? His answer is absolute: certainly not. The real problem would be to rebuild the law-based barriers that had been torn down as the basis of righteous standing and fellowship. If someone rebuilds those old barriers, he shows himself to be the transgressor.

Paul explains why. Through the law, he died to the law so that he might live to God. The law no longer stands as the basis of his acceptance and status. That is why Paul can say, I have been crucified with Christ. This is not mystical exaggeration or merely an inward feeling. It means that through union with Christ, Paul’s old relation to the law as the ground of status has come to an end. His life is now defined by Christ himself.

So Paul can say, It is no longer I who live, but Christ lives in me. He still lives an earthly life in the body, but its source and direction have changed. He now lives by faith in the Son of God, by ongoing trust in the Son who loved him and gave himself for him. Christ’s self-giving death is not an abstract doctrine. It is the decisive act of love that now governs the believer’s life.

Paul closes with a sharp conclusion: he will not set aside the grace of God. If righteousness could come through the law, then Christ died for nothing. That would empty the cross of its necessity and deny grace at its core. So the Antioch incident was not a minor dispute between church leaders. It exposed a practical denial of the gospel itself. To rebuild law-based barriers as the ground of acceptance is to contradict justification by faith and to dishonor the grace of God in Christ.

Key Truths: - Peter’s withdrawal from Gentile believers was a public denial of the gospel’s implications. - The text does not show that James himself supported the separatist behavior. - Paul’s concern is not mere etiquette but conduct that contradicted the truth of the gospel. - Justification means being declared righteous before God. - No one is justified by works of the law; justification is through faith in Christ, grounded in Christ’s self-giving work. - In this passage, works of the law includes Jewish law-shaped boundary markers, though Paul’s point also reaches more broadly to law-keeping as a basis of acceptance before God. - Union with Christ means the believer’s old standing under the law has ended, and a new life has begun in him. - If righteousness could come through the law, Christ’s death would be unnecessary.