We study what Paul says to Peter to show why he was wrong to withdraw from eating with the Gentile believers. If the Gospel of Grace is true, then God has fully accepted the Gentiles, on the basis of their faith in Christ. Therefore, Jews and Gentiles are equal in Christ, and so separation on the basis of race is a sin, and a denial of the Gospel. In these key verses, Paul summarises the truths that lie at the heart of Galatians, which he will develop in later chapters. He establishes that we are justified before God by faith in Christ and not works of law, and explains why we are no longer under the jurisdiction and condemnation of the law. He also counters the objection that justification by faith alone encourages a sinful lifestyle, by revealing the transformation that takes place in us when we are put into Christ, for now Christ lives in us! Finally he points out that if we maintain that justification is by our works, then we would be guilty of devaluing, rejecting and setting aside the grace of God, and asserting that Christ died in vain, that His death on the Cross was superfluous.