Genesis 17:26 in the World English Bible
In the same day both Abraham and Ishmael, his son, were circumcised.
Context
25 And Ishmael his son was thirteen years old, when he was circumcised in the flesh of his foreskin.
26 In the selfsame day was Abraham circumcised, and Ishmael his son.
27 And all the men of his house, born in the house, and bought with money of the stranger, were circumcised with him.