The situation in Galatia must have been confusing, on one hand Paul, the brother who brought the Galatians to Christ taught that they must live by faith and focus solely on Christ. On the other hand, different brothers came in and added teachings beyond what Paul had taught, saying they must continue in things such as circumcision, feasts, and other rituals of the law. How did the Galatians know what to believe?

In verses 8 and 9 Paul makes an extremely bold declaration concerning his gospel, saying anyone that adds anything further should be accursed. After making such a strong statement, he begins to give equally strong support for his statement, revealing that the source of his gospel is not man, but God Himself. If God truly is the source of his gospel, who can argue? In addition, he shows that he is a good “carrier” of this gospel by not adding anything to the word of God just to please men or win the assent of men.

trying to win the assent of men...trying to please men - Paul did not operate according to man’s approval. Many brothers felt what Paul taught was against God’s command and rose up to persecute him. However, Paul never added anything to the revelation just to appease the religious. Because of this, Paul was a good carrier of the gospel because he lived only for God’s approval. (1 Thess 2:4)

slave of Christ – Paul was a true slave of Christ, doing the will of his master no matter what the cost. Galatians 6:17 says, “I bear in my body the brands of Jesus”. Paul not only saw a revelation, but was willing to pay such a high price. On the contrary, other brothers were seeking man’s agreement by adding things to the gospel such as the need to be circumcised. These brothers were slaves of men adding things because of the fear of being persecuted for teaching what was not popular with God’s people (6:13).

not according to man – Paul’s gospel was not in the realm of man and was not according to man’s concept. According to man’s concept we should do something for God in order to be saved. Paul’s gospel was of grace and was completely outside of man’s way of thinking.

neither did I receive it from man nor was I taught it – Paul’s gospel did not originate through any man, including himself. It wasn’t the product of human wisdom nor did he receive it as something passed down through other apostles.

I received it through a revelation by Jesus Christ – The source of Paul’s gospel was Jesus Christ! Paul’s defense of his gospel went straight to the source. Since the gospel Paul preached was a dispensational change it was originated directly from Jesus Christ through a revelation.