And Moses took the blood and sprinkled it on the people, and said, Behold the blood of the covenant, which Jehovah has made with you concerning all these words.
Then Jesus says to them, Truly, truly, I say to you, Unless you eat the flesh of the Son of Man, and drink His blood, you do not have life in yourselves.
The cup of blessing which we bless, is it not the communion of the blood of Christ? The bread which we break, is it not the communion of the body of Christ?
In the same way He took the cup also, after supping, saying, "This cup is the New Covenant in My blood; as often as you drink it, do this in remembrance of Me."