Genesis 17:12-13
Genesis 17:12-13 ASV
And he that is eight days old shall be circumcised among you, every male throughout your generations, he that is born in the house, or bought with money of any foreigner that is not of thy seed. He that is born in thy house, and he that is bought with thy money, must needs be circumcised: and my covenant shall be in your flesh for an everlasting covenant.