Note 1 at Ga 1:6: Normally, Paul opened his letters with thanksgiving, prayer, and praise for the saints within his salutation (1Co 1:1-5, Php 1:1-5, Col 1:1-4, 1Th 1:1-3, 2Th 1:1-3, and 2Ti 1:1-3). In this letter to the Galatians, Paul dispensed with polite introductions after only one sentence (Ga 1:1-5). He quickly delivered a stinging curse against anyone who would dare to preach a gospel other than what Paul had preached (Ga 1:8-9). This, no doubt, shocked the Galatians and held their attention throughout the rest of the letter.

In his letter to the Galatians, Paul basically dealt with the same truths as presented in Romans, Ephesians, Colossians, and Hebrews, but he delivered these truths in a near-brutal way that he didn't employ in those other letters. Paul was very concerned that the Galatians had, or would soon, fall from grace (Ga 4:11 and 5:2-4).

Note 2 at Ga 1:6: The Greek word translated "marvel" in this verse is "THAUMAZO," and it carries the idea of that which would evoke surprise. It is rendered in various translations as the phrases "I marvel" (King James Version), "I am amazed" (The Living Bible), "I am astonished" (New International Version), and "I am surprised at you!" (Today's English Version). Why was Paul surprised? Not because they were deserting some doctrine of theology, but because they were deserting God himself. Whenever people remove themselves from the grace that is revealed in Christ, they remove themselves from God Himself.

Note 3 at Ga 1:6: Certainly, Paul had experienced people falling away from their faith in Christ to follow the self-salvation that he denounced in this letter. However, he was shocked to see how soon it had happened with the Galatians.

Note 4 at Ga 1:6: In the Greek, the removing that Paul was rebuking is in the present tense; this indicates that the removing is in progress but is not yet complete. In other words, the Galatians were in a state of double-mindedness with their ears turned toward a false gospel. Paul was going to do everything he could through this letter to turn their hearts back to God.

Note 5 at Ga 1:6: Paul used the words "grace" and "gospel" interchangeably in this verse. The grace of God is the Gospel (see note 5 at Ac 20:24). Without grace, there is no good news for a sinful world.

Note 6 at Ga 1:6: Two different Greek words were used in Ga 1:6-7 for the English word "another." In Ga 1:6, the Greek word for "another" is "HETEROS," and it means "another of a different sort" (Vine's Expository Dictionary, emphasis mine). That's why the New International Version translated this phrase as "turning to a different gospel" (emphasis mine). The Greek adjective used in Ga 1:7 for "another" is "ALLOS," and it means "another of the same kind" (Vine's Expository Dictionary, emphasis mine). The Galatians were not turning toward a gospel that was similar in nature to the one they had already received. They were turning to a totally different gospel that Ga 1:7 states "is really no gospel at all" (NIV).

Paul made it very clear in Ro 11:6 that we are either saved by grace or by works, but not by a combination of the two (see note 2 at Ro 11:6). So, any gospel that combines works of the Law with grace for justification is no longer the same Gospel. In other words, Paul was saying that there is no room for additions or corrections to the Gospel of grace that he preached. It is perfect as presented. Any change perverts it.