Galatians 5:3-4

The Galatians would be obligating themselves to obey the whole Mosaic Code if they allowed the false teachers to circumcise them. [Note: Lightfoot, p. 203.] Their confidence in circumcision would reveal confidence in their own ability to earn salvation by obeying the Law. This legal approach to salvation would separate them from Christ since what He did was provide salvation as a gift. They would fall away from the grace method of salvation if they chose the law method. " Grace" was a favorite word of Paul’s. He used it 100 of the 155 times it occurs in the New Testament. In view of the many scriptural promises that God never withdraws His gift of salvation, Galatians 5:4 cannot mean the readers had lost their salvation (e.g., John 1:12; John 3:16; John 3:36; John 5:24; John 6:47; John 10:28-29; Romans 8:31-39; et al.).

The legalists appear to have been claiming that circumcision was a necessary step in the process by which people become acceptable to God. These steps from their viewpoint were faith in Christ, reception of the Spirit, and circumcision of the flesh. Paul argued that anyone who submits to circumcision to gain acceptance with God really believes in salvation by law-keeping. If one believes in law-keeping for salvation, he must keep the whole Law, not just the requirement of circumcision. That is impossible for sinners to do. Rather than gaining acceptance with God, circumcision would be what separated them from Christ.