Genesis 17:23-27

So without delay Abraham obeyed God and took his son Ishmael and every male in his household (whether born in his house or foreign-born servants) and circumcised them that very same day. Abraham was already ninety-nine years old when he was circumcised, and his son Ishmael was thirteen. They were both circumcised on the same day, along with all the men of his household (whether born in his house or foreign-born servants).