1 Corinthians 11:26-28

Young's Literal Translation

²⁶ for as often as ye may eat this bread, and this cup may drink, the death of the Lord ye do shew forth -- till he may come;

²⁷ so that whoever may eat this bread or may drink the cup of the Lord unworthily, guilty he shall be of the body and blood of the Lord:

²⁸ and let a man be proving himself, and so of the bread let him eat, and of the cup let him drink;