Exodus 12:48-50 Modern English Version (MEV)
48 Now when a stranger sojourns with you and keeps the Passover to the Lord, let all his males be circumcised, and then let him come near and keep it. And he shall be as one that is born in the land. However, no uncircumcised person shall eat of it. 49 The same law shall apply to him that is a native and to the stranger who sojourns among you.
50 So all the children of Israel did it. They did just as the Lord commanded Moses and Aaron.