'Circumcised' in the Bible

And he gave him the covenant of circumcision: and so Abraham begat Isaac, and circumcised him the eighth day; and Isaac begat Jacob, and Jacob the twelve patriarchs.

And certain men came down from Judaea and taught the brethren,'saying , Except ye be circumcised after the custom of Moses, ye cannot be saved.

Him would Paul have to go forth with him; and he took and circumcised him because of the Jews that were in those parts: for they all knew that his father was a Greek.