The Circumstance of Paul's Confrontation of Peter

Paul ended his rehearsal of his background with an account of his confrontation of Peter at Antioch. This episode was the context for his treatment of the doctrine of "justification by faith" in the Galatian epistle, and so it's crucially important to understand what was happening at Antioch with Peter in order to understand what Paul meant by this doctrine and how it pertained to the circumstance at hand.