Exodus 12:48-50 Revised Standard Version Catholic Edition (RSVCE)
48 And when 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 shall be as a native of the land. But no uncircumcised person shall eat of it. 49 There shall be one law for the native and for the stranger who sojourns among you.”
50 Thus did all the people of Israel; as the Lord commanded Moses and Aaron, so they did.