Genesis 17:9-11

New Revised Standard Version, Anglicised

⁹ God said to Abraham, ‘As for you, you shall keep my covenant, you and your offspring after you throughout their generations. ¹⁰ This is my covenant, which you shall keep, between me and you and your offspring after you: Every male among you shall be circumcised. ¹¹ You shall circumcise the flesh of your foreskins, and it shall be a sign of the covenant between me and you.