ACT 7:8

8 “Then God commanded Abraham that [every male in his household and all of his male descendants] should be circumcised [to show that they all belonged to God] and that they would obey what he had told Abraham to do. Later Abraham’s son, Isaac, was born, and when Isaac was eight days old, Abraham circumcised him. [Later] Isaac’s son, Jacob, was born, and Isaac [similarly circumcised] him. And Jacob [similarly circumcised] his twelve sons. They are the twelve men [from whom we(inc) Jews have all descended].”