In Galatians 2, Paul confronts Peter—not because Peter preached a false gospel, but because he wasn’t living in line with the gospel. By separating himself from Gentile believers, Peter sent the wrong message: that obedience to the law was still necessary for acceptance with God. Paul uses this moment to make the gospel crystal clear—we are made right with God (justified) by faith in Christ alone, not by anything we do. And when our actions contradict that truth, we must correct them—because our lives preach, even when our mouths don’t.