Recent research into the character of Judaism in the first century has given scholars a new perspective on Paul. Nowhere is this new perspective more important than in the case of Paul's letter to the Galatians, a letter that shaped the character of the Christian religion in its early years and that remains a foundation document of Christianity. This study, the first to benefit from the new perspective on Paul, explains more clearly than ever the issues that confronted Paul and the powerful theological arguments he brought to bear in response.