Galatians

NEXT TO ROMANS, NO OTHER WRITING has impacted the shape of reformed theology more than Paul's letter to the Galatians. So important was the letter that Luther affectionately referred to it as his Katie von Bora - the name of his wife, stating that in some ways he was married to the letter as well.
Like Romans, Galatians is rooted in Paul's conviction that through the resurrection of Jesus, God's new creation has burst in upon the old with redeeming power and vindication for those made part of Christ's body by faith.
Unlike Romans however, Galatians isn't primarily an exposition on the gospel or how we get saved. Rather, what is really at issue is the inclusion of all people in the single, multi-ethnic family of God. Who is in and who is out? Who belongs? And on what basis? These are the real issues being debated by the churches to whom Paul is writing.
Paul's answer is that men and women are made part of the community of Christ by faith alone and not works of the Law. Followers of Jesus, no matter what their ethnic or moral background is, are incorporated into the family of God by the grace and action of God alone, and not by outward marks of Jewish identity.
In Galatians: A Commentary, pastor and author Marc Simon offers a verse by verse exposition of Galatians which is at once accessible to scholars, pastors, and students alike.