1 Corinthians 11:20-29 When you come together therefore into one place, this is not to eat the Lord's supper. For in eating every one takes first his own supper: and one is hungry, and another is drunken. What? have you not houses to eat and to drink in? or despise you the church of God, and shame them that have not? What shall I say to you? shall I praise you in this? I praise you not. For I have received of the Lord that which also I delivered unto you, That the Lord Jesus the same night in which he was betrayed took bread: And when he had given thanks, he broke it, and said, Take, eat: this is my body, which is broken for you: this do in remembrance of me. After the same manner also he took the cup, after he had eaten, saying, This cup is the new testament in my blood: this do you, as often as you drink it, in remembrance of me. For as often as you eat this bread, and drink this cup, you do show the Lord's death till he comes. Therefore whosoever shall eat this bread, and drink this cup of the Lord, unworthily, shall be guilty of the body and blood of the Lord. But let a man examine himself, and so let him eat of that bread, and drink of that cup. For he that eats and drinks unworthily, eats and drinks judgment to himself, not discerning the Lord's body.
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Matthew 26:26-28 And as they were eating, Jesus took bread, and blessed it, and broke it, and gave it to the disciples, and said, Take, eat; this is my body. And he took the cup, and gave thanks, and gave it to them, saying, Drink you all of it; For this is my blood of the new covenant, which is shed for many for the remission of sins.
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Mark 14:22-25 And as they did eat, Jesus took bread, and blessed, and broke it, and gave to them, and said, Take, eat: this is my body. And he took the cup, and when he had given thanks, he gave it to them: and they all drank of it. And he said unto them, This is my blood of the new covenant, which is shed for many. Verily I say unto you, I will drink no more of the fruit of the vine, until that day that I drink it new in the kingdom of God.
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Luke 22:17-20 And he took the cup, and gave thanks, and said, Take this, and divide it among yourselves: For I say unto you, I will not drink of the fruit of the vine, until the kingdom of God shall come. And he took bread, and gave thanks, and broke it, and gave unto them, saying, This is my body which is given for you: this do in remembrance of me. Likewise also the cup after supper, saying, This cup is the new covenant in my blood, which is shed for you.
There are a few passages about this to start.
