Exodus 12:48-50 New King James Version (NKJV)

48. And when a stranger dwells with you and wants to keep 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 a native of the land. For no uncircumcised person shall eat it.

49. One law shall be for the native-born and for the stranger who dwells among you.”

50. Thus all the children of Israel did; as the Lord commanded Moses and Aaron, so they did.

Exodus 12