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27Wherefore whosoever shall eat the bread or drink the cup of the Lord in an unworthy manner, shall be guilty of the body and the blood of the Lord. 28But let a man prove himself, and so let him eat of the bread, and drink of the cup. 29For he that eateth and drinketh, eateth and drinketh judgment unto himself, if he discern not the body.
1 Corinthians 11:27-29 (ASV)