Circumcised

Genesis 17:9-11 (ESV)

9 And 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 be circumcised in the flesh of your foreskins, and it shall be a sign of the covenant between me and you.

Genesis 17:19 (ESV)

God said, “No, but Sarah your wife shall bear you a son, and you shall call his name Isaac. I will establish my covenant with him as an everlasting covenant for his offspring after him.

The Abrahamic covenant was for His descendants of the flesh. Throughout the generations, every male was to be circumcised as the sign of an everlasting covenant. And so it is. Isaac and Ishmael were both circumcised and so are their descendants of the covenant. 

A new covenant would be established with the seed of Isaac. He is the promised son from whose seed would come the Son of promise who is the seed of the word of God. The offspring of that covenant would be circumcised in the heart, male and female, in an everlasting covenant of eternal life.