17:23And Abraham took Ishmael his son, and all that were born in his house, and all that were bought with his money, every male among the men of Abraham's house; and circumcised the flesh of their foreskin in the selfsame day, as God had said unto him.

17:24And Abraham was ninety years old and nine, when he was circumcised in the flesh of his foreskin.

17:25And Ishmael his son was thirteen years old, when he was circumcised in the flesh of his foreskin.

17:26In the selfsame day was Abraham circumcised, and Ishmael his son.

17:27And all the men of his house, born in the house, and bought with money of the stranger, were circumcised with him.

21:3And Abraham called the name of his son that was born unto him, whom Sarah bare to him, Isaac.

21:4And Abraham circumcised his son Isaac being eight days old, as God had commanded him.