Galatians

An introduction situating Paul's letter in time and space is followed by a detailed discussion of each section of the letter, verse-by-verse commentary, and a theological discussion with challenging questions for individual or group study.
From the Introduction:

Luther and Calvin tended to read the letter as having primarily to do with justification by works or by faith. But that is decidedly not the matter that called forth this letter, which is stated most clearly in one of the opening sentences of the argument proper: "Having begun by the Spirit, are you now trying to finish by means of the flesh?" (1:3), where "flesh" is a play on words, referring to literal circumcision of the flesh as the primary issue regarding their "keeping" the law.

At issue throughout the letter is not the question, "How are people saved?" (to use contemporary language) but whether people who are already "saved" also need to practice specific aspects of the Jewish law. The concern, then, is not how one begins life in Christ, but whether, once begun, one must also add these aspects of the law to be completed in one's faith in Christ.