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26For as often as ye eat this bread, and drink the cup, ye proclaim the Lord`s death till he come. 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.
1 Corinthians 11:26-28 (ASV)