'Drink the Cup' in the Bible

Ye cannot drink the cup of the Lord, and the cup of demons: ye cannot partake of the table of the Lord, and of the table of demons.

For as often as ye eat this bread, and drink the cup, ye proclaim the Lord's death till he come.

Wherefore 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.