But I make known to you, brethren, that the gospel which was preached by me is not according to man.
(Galatians 1:11 NKJV)

the gospel is not from man but by the revelation of Jesus Christ

1. The Galatian brothers have taken a giant step in the wrong direction. They are in the process of apostasy and therefore of being accursed (1:6-9). They illustrate what falling from grace looks like. (“You have become estranged from Christ, you who attempt to be justified by law; you have fallen from grace” – Galatians 5:4).
2. Paul wants these confused brothers to know that his gospel is not of his own invention. It came by the revelation of Jesus Christ (Galatians 1:12). If they reject his teaching, they reject Christ Himself. “He who rejects Me, and does not receive My words, has that which judges him — the word that I have spoken will judge him in the last day” (John 12:48).
3. Like many today, the Galatians think they are safe in choosing what they want to believe. If they ate after this manner, they would just as soon pick poison as wholesome food.

-- Rick Duggin