For as often as you eat this bread, and drink this cup, you do show the Lord's death till he comes. Therefore whosoever shall eat this bread, and drink this cup of the Lord, unworthily, shall be guilty of the body and blood of the Lord. But let a man examine himself, and so let him eat of that bread, and drink of that cup. For he that eats and drinks unworthily, eats and drinks judgment to himself, not discerning the Lord's body.
(1 Corinthians 11:26-29)