Genesis 17:23-27

23Then Abraham took Ishmael his son and all those born in his house or bought with his money, every male among the men of Abraham’s house, and he circumcised the flesh of their foreskins that very day, as God had said to him. 24Abraham was ninety-nine years old when he was circumcised in the flesh of his foreskin. 25And Ishmael his son was thirteen years old when he was circumcised in the flesh of his foreskin. 26That very day Abraham and his son Ishmael were circumcised. 27And all the men of his house, those born in the house and those bought with money from a foreigner, were circumcised with him.