Paul's confrontation with Peter in Antioch over eating with Gentiles reveals how even apostles can compromise gospel truth under social pressure from legalistic believers. His argument that justification comes through faith in Christ rather than works of law establishes the theological foundation for Gentile freedom from Jewish ceremonial requirements. The Jerusalem leaders' recognition of Paul's ministry to the Gentiles confirms the legitimacy of his law-free gospel while maintaining unity between Jewish and Gentile missions.