Exodus 12:48-49

CAB(i) 48 And if any proselyte shall come to you to keep the Passover to the Lord, you shall circumcise every male of him, and then shall he approach to sacrifice it, and he shall be even as the original inhabitant of the land; no uncircumcised person shall eat of it. 49 There shall be one law to the native, and to the proselyte coming among you.