And when a foreigner shall sojourn with you, and will 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 one that is born in the land: for no uncircumcised person shall eat of it.
All Commentaries on Exodus 12:48 Go To Exodus 12
George Leo Haydock
Dwell, or become a proselyte, by circumcision, if a male; or by baptism, if a female; receiving a sort of new-birth, John iii. 10. The Jews would not suffer any to dwell among them, who would not observe the seven precepts given to Noe, Genesis ix. But the proselytes of justice embraced the Jewish religion. (Calmet)