Genesis 17:23

23Then Abraham took Ishmael his son and all those born in his house or bought with his money, every male among the men of Abraham’s house, and he circumcised the flesh of their foreskins that very day, as God had said to him.

Exodus 12:48-49

48 aIf a stranger shall sojourn with you and would keep the Passover to the Lord, let all his males be circumcised. Then he may come near and keep it; he bshall be as a native of the land. But no uncircumcised person shall eat of it. 49There shall be cone law for the native and for the dstranger who sojourns among you.”

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