VERSE 7. And would pervert the gospel of Christ.
To paraphrase this sentence: "These false apostles do not merely trouble you, they abolish Christ's Gospel. They act as if they were the only true Gospel-preachers. For all that they muddle Law and Gospel. As a result they pervert the Gospel. Either Christ must live and the Law perish, or the Law remains and Christ must perish; Christ and the Law cannot dwell side by side in the conscience. It is either grace or law. To muddle the two is to eliminate the Gospel of Christ entirely."
It seems a small matter to mingle the Law and Gospel, faith and works, but it creates more mischief than man's brain can conceive. To mix Law and Gospel not only clouds the knowledge of grace, it cuts out Christ altogether.
The words of Paul, "and would pervert the gospel of Christ," also indicate how arrogant these false apostles were. They were shameless boasters. Paul simply had to exalt his own ministry and Gospel.
VERSE 8. But though we, or an angel from heaven, preach any other gospel unto you than that which we have preached unto you, let him be accursed.
Paul's zeal for the Gospel becomes so fervent that it almost leads him to curse angels. "I would rather that I, my brethren, yes, the angels of heaven be anathematized than that my gospel be overthrown."
The Greek word anathema, Hebrew herem, means to accurse, execrate, to damn. Paul first (hypothetically) curses himself. Knowing persons first find fault with themselves in order that they may all the more earnestly reprove others.
Paul maintains that there is no other gospel besides the one he had preached to the Galatians. He preached, not a gospel of his own invention, but the very same Gospel God had long ago prescribed in the Sacred Scriptures. No wonder Paul pronounces curses upon himself and upon others, upon the angels of heaven, if anyone should dare to preach any other gospel than Christ's own.
VERSE 9. As we said before, so say I now again. If any man preach any other gospel unto you than that ye have received, let him be accursed.
Paul repeats the curse, directing it now upon other persons. Before, he cursed himself, his brethren, and an angel from heaven. "Now," he says, "if there are any others who preach a gospel different from that you have received from us, let them also be accursed." Paul herewith curses and excommunicates all false teachers including his opponents. He is so worked up that he dares to curse all who pervert his Gospel. Would to God that this terrible pronouncement of the Apostle might strike fear into the hearts of all who pervert the Gospel of Paul.