Jesus and the New Creation
Paul draws on the themes from the letter (salvation by faith in Christ's work on the cross, apart from any works of the flesh) and points his readers towards the new creation through Christ's work. He makes it very plain that his opponents seek to glory in their flesh but that God's people glory in the cross alone. Whereas the Judaizers would boast in the marks of circumcision that they inflicted upon their own bodies, Paul indicates that the true marks of following Jesus are the marks of persecution inflicted upon him by others for preaching grace alone. We must not boast in ourselves, but we boast in the cross of Christ.