Can’t eat the passover sacrifice if the person is unclean, just as can’t commune if in state of mortal sin. Terrible consequences for both:
Lv 7:19b-21 All who are clean may eat flesh, but the person who eats of the flesh of the sacrifice of the Lord’s peace offerings while an uncleanness is on him, that person shall be cut off from his people. And if any one touches an unclean thing, whether the uncleanness of man or an unclean beast or any unclean abomination, and then eats of the flesh of the sacrifice of the Lord’s peace offerings, that person shall be cut off from his people.
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The need for Baptism for the Eucharist:
Ex 12:48 And when a stranger shall sojourn with you and would keep the passover to the Lord, let all his males be circumcised, then he may come near and keep it; he shall be as a native of the land. But no uncircumcised person shall eat of it.
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