Genesis 17:23-27

On that very day Abraham took his son Ishmael and all those born in his household or bought with his money, every male in his household, and circumcised them, as God told him. Abraham was ninety-nine years old when he was circumcised, and his son Ishmael was thirteen; Abraham and his son Ishmael were both circumcised on that very day. And every male in Abraham’s household, including those born in his household or bought from a foreigner, was circumcised with him.