1 Corinthians 11:25-27 - WEB
25
In the same way he also took the cup, after supper, saying, "This cup is the new covenant in my blood. Do this, as often as you drink, in memory of me."
26
For as often as you eat this bread, and drink this cup, you proclaim the Lord`s death until he comes.
27
Therefore whoever eats this bread or drinks the Lord`s cup in an unworthy manner, will be guilty of the body and the blood of the Lord.
Full Chapter