On the first day of the Feast of Unleavened Bread, when it was customary to sacrifice the Passover lamb, Jesus' disciples asked him, "Where do you want us to go and make preparations for you to eat the Passover?"
So he sent two of his disciples, telling them, "Go into the city, and a man carrying a jar of water will meet you. Follow him. Say to the owner of the house he enters, 'The Teacher asks: Where is my guest room, where I may eat the Passover with my disciples?' He will show you a large upper room, furnished and ready. Make preparations for us there." The disciples left, went into the city and found things just as Jesus had told them. So they prepared the Passover.
While they were eating, Jesus took bread, gave thanks and broke it, and gave it to his disciples, saying, "Take it; this is my body."
1 Corinthians 10:16
Is not the cup of thanksgiving for which we give thanks a participation in the blood of Christ? And is not the bread that we break a participation in the body of Christ?
1 Corinthians 11:27-29 Therefore, whoever eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty of sinning against the body and blood of the Lord. A man ought to examine himself before he eats of the bread and drinks of the cup. For anyone who eats and drinks without discerning the body of the Lord eats and drinks judgment on himself.
Then he took the cup, gave thanks and offered it to them, and they all drank from it. "This is my blood of the covenant, which is poured out for many," he said to them.
The time is coming," declares the LORD, "when I will make a new covenant with the house of Israel and with the house of Judah. It will not be like the covenant I made with their forefathers when I took them by the hand to lead them out of Egypt… This is the covenant I will make with the house of Israel after that time... I will forgive their wickedness and will remember their sins no more.
"I tell you the truth, I will not drink again of the fruit of the vine until that day when I drink it anew in the kingdom of God."