Galatians 1:8-9; Galatians 1:12; Galatians 3:11

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. 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.
12 For I neither received it of man, neither was I taught it, but by the revelation of Jesus Christ.
11 But that no man is justified by the law in the sight of God, it is evident: for, The just shall live by faith.