For before that certain came from James, he did eat with the Gentiles: but when they were come, he withdrew and separated himself, fearing them which were of the circumcision. Before that certain came from James, he did eat with the Gentiles - Here was Peter's fault. He was convinced that God had pulled down the middle wall of partition that had so long separated the Jews and Gentiles, and he acted on this conviction, associating with the latter and eating with them; but when certain Jews came from James, who it appears considered the law still to be in force, lest he should place a stumbling-block before them he withdrew from all commerce with the converted Gentiles, and acted as if he himself believed the law to be still in force, and that the distinction between the Jews and the Gentiles should still be kept up.
Related Commentaries of Galatians 2:12
Galatians 2:12
12 For before that certain came from James, he did eat with the Gentiles: but when they were come, he withdrew and separated himself, fearing them which were of the circumcision.