What does Exodus 12:48 mean?

If a foreigner is living with you and wants to celebrate the Passover to honor the Lord, every man in his household has to be circumcised first. Then he can join in and be treated like someone born in Israel. But if he isn't circumcised, he can't eat it. Exodus 12:48 - Modern Text Bible

(Foreigners could join in if they fully committed to the community and its covenant, but not otherwise.)