Genesis 17:25-27

New Revised Standard Version, Anglicised

²⁵ And his son Ishmael was thirteen years old when he was circumcised in the flesh of his foreskin. ²⁶ That very day Abraham and his son Ishmael were circumcised; ²⁷ and all the men of his house, slaves born in the house and those bought with money from a foreigner, were circumcised with him.