'Of the Circumcision' in the Bible

But on the contrary, when they saw that the gospel of the uncircumcision was committed unto me, as the gospel of the circumcision was unto Peter;

(For he that worked effectually in Peter to the apostleship of the circumcision, the same was mighty in me toward the Gentiles:)

For before certain men came from James, he did eat with the Gentiles: but when they were come, he withdrew and separated himself, fearing them who were of the circumcision.