Because Jesus did not officially name the ceremony, different churches and sects came up with their own terminology.
The term Communion is derived from Latin communio ("sharing in common"), translated from the Greek κοινωνία (koinōnía) in 1 Corinthians 10:16:
"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?"
For the sake of this article I will refer to the ceremony as "communion".
The original supper
Now as they were eating, Jesus took bread, and after blessing it broke it and gave it to the disciples, and said, “Take, eat; this is my body.” And he took a cup, and when he had given thanks he gave it to them, saying, “Drink of it, all of you, for this is my blood of the covenant, which is poured out for many for the forgiveness of sins. -- Matthew 26:26-28 (ESV)
And he took a cup, and when he had given thanks he said, “Take this, and divide it among yourselves. For I tell you that from now on I will not drink of the fruit of the vine until the kingdom of God comes.” And he took bread, and when he had given thanks, he broke it and gave it to them, saying, “This is my body, which is given for you. Do this in remembrance of me.” And likewise the cup after they had eaten, saying, “This cup that is poured out for you is the new covenant in my blood. -- Luke 22:17-20 (ESV)
And as they were eating, he took bread, and after blessing it broke it and gave it to them, and said, “Take; this is my body.” And he took a cup, and when he had given thanks he gave it to them, and they all drank of it. And he said to them, “This is my blood of the covenant, which is poured out for many. Truly, I say to you, I will not drink again of the fruit of the vine until that day when I drink it new in the kingdom of God.” -- Mark 14:22-25 (ESV)
Now as they were eating,
Jesus took bread, and after blessing it broke it and gave it to the disciples, and said,
“Take, eat. This is my body, which is given for you. Do this in remembrance of me.”
And he took a cup, and when he had given thanks he gave it to them, and they all drank of it. And he said to them,
“This is my blood of the covenant, which is poured out for many. Take this, and divide it among yourselves. Truly, I tell you, from now on I will not drink again of the fruit of the vine until that day when I drink it new in the kingdom of God.”
How to serve Communion
Paul warns against serving the Communion incorrectly. It seems like Paul implied that the church of Corinthians were very selfish by allowing gluttony and drunkness to take over at the feast so that those who came late would go hungry. In addition to that it also seems like they would "even humiliate those who had nothing" so that they would in return "despise" those who consumed all the food and drinks.
When you come together, it is not the Lord's supper that you eat. For in eating, each one goes ahead with his own meal. One goes hungry, another gets drunk. What! Do you not have houses to eat and drink in? Or do you despise the church of God and humiliate those who have nothing? What shall I say to you? Shall I commend you in this? No, I will not. -- 1 Corinthians 11:20-22 (ESV)
Out of context, it would seem that Paul is implying with his question "Do you not have houses to eat and drink in?" That one should eat and drink at home before attending the Communion ceremony. However, Jesus' own disciples were "eating" while he served the "Lord's Supper" (Matthew 26:26; Mark 14:22).
The point Paul is trying to make is that believers are supposed to wait for each other, and share the food and drinks with one another so that they could have fellowship.
So then, my brothers, when you come together to eat, wait for one another — if anyone is hungry, let him eat at home — so that when you come together it will not be for judgment. -- 1 Corinthians 11:33-34 (ESV)
In the previous chapter Paul made the point:
The cup of blessing that we bless, is it not a participation in the blood of Christ?
The bread that we break, is it not a participation in the body of Christ? Because there is one bread, we who are many are one body, for we all partake of the one bread.
-- 1 Corinthians 10:16-17 (ESV)
The English word "participation" comes from the Greek word "koinōnía" (communion) which actually means:
- social intercourse
Jesus could have chosen to serve Communion in the temple, but he chose a house (Matthew 26:18). It is very likely that the first disciples continued the tradition in houses (Acts 20:7-11) and not temples or church buildings.
Therefore, Communion is supposed to be an informal feast potentially at someone's house. Believers should at least wait for each other so that they could share the food and drinks and have social intercourse and fellowship without despising each other.
The purpose of Communion
Aside from fellowship with fellow believers, the purpose of this ceremony is...
Whoever, therefore, eats the bread or drinks the cup of the Lord in an unworthy manner will be guilty concerning the body and blood of the Lord.
Let a person examine himself, then, and so eat of the bread and drink of the cup. For anyone who eats and drinks without discerning the body or his flesh eats and drinks judgment on himself. That is why many of you are weak and physically or mentally ill, and some have died fallen asleep. But if we judged ourselves truly, we would not be judged. But when we are judged by the Lord, we are disciplined so that we may not be condemned along with the world.
So then, my brothers, when you come together to eat, wait for one another — if anyone is hungry, let him eat at home — so that when you come together it will not be for judgment.
-- 1 Corinthians 11:23-34 (ESV)
Some understand this means that if they do participate in Communion, but follow the ritual incorrectly, God will punish you with weakness, sickness or even death. These people tend to avoid Communion in fear of getting punished by God.
Other understand this means that if they do not participate in Communion, they will not be under God's protection and as a result they could become weak, ill and die. These people strictly follow only the rituals in fear of the curse and miss out of the fellowship.
This is because some bible translators translated the Greek word "κοιμῶνται" as "death", but the actual meaning is "fallen asleep". If Paul meant physical death he would have more likely used the same Greek word "θάνατον" for death as he did in verse 26.
Those participating ought to examine themselves, repenting as sinners in their flesh (translated as "the body") so that those who observe the Communion can understand why they need the blood and the body of the Lord.
Some badly translated English bibles read:
For anyone who eats and drinks without discerning the body eats and drinks judgment on himself. -- 1 Corinthians 11:30 (ESV)
Usually body mean "the church" and out of context one could easily make the mistake to think that one should discern other church members or that one ought not to participate Communion outside a church.
However, it would be impossible and unfair from the Lord to expect us to judge other church members' hidden sin or intentions to participate in Communion. If this was true, then Jesus himself would be in trouble because he participated in Communion with Judas Iscariot who betrayed him that very same night (1 Corinthians 11:23) even when Jesus knew he would do it (Matthew 26:21-25).
In the context of self-examination, Paul more likely meant you need to discern your own flesh (or sinful nature).
If you intend to become intimate with someone you are not in good standing with, you will offend the person.
Only after self-examination and good standing with the Christ, one can enjoy an...
Intimate relationship with Jesus
So Jesus said to them,
“Truly, truly, I say to you, unless you eat the flesh of the Son of Man and drink his blood, you have no life in you.
- Whoever feeds on my flesh and drinks my blood has eternal life, and I will raise him up on the last day. For my flesh is true food, and my blood is true drink.
- Whoever feeds on my flesh and drinks my blood abides in me, and I in him. As the living Father sent me, and I live because of the Father, so whoever feeds on me, he also will live because of me. This is the bread that came down from heaven, not like the bread the fathers ate, and died.
- Whoever feeds on this bread will live forever.” -- John 6:52-58 (ESV)
In other words, Communion is a very intimate act with the Jesus, the Son of Man as it touches his flesh and his blood. You cannot be intimate with someone if you did not examine yourself and if you are not in good standing with the person.
The is because Jesus identified himself as:
Do not work for the food that perishes, but for the food that endures to eternal life, which the Son of Man will give to you. -- John 6:27 (ESV)
Jesus then said to them, “Truly, truly, I say to you, it was not Moses who gave you the bread from heaven, but my Father gives you the true bread from heaven. For the bread of God is he who comes down from heaven and gives life to the world.”
They said to him, “Sir, give us this bread always.”
Jesus said to them, “I am the bread of life; whoever comes to me shall not hunger, and whoever believes in me shall never thirst. But I said to you that you have seen me and yet do not believe. All that the Father gives me will come to me, and whoever comes to me I will never cast out. For I have come down from heaven, not to do my own will but the will of him who sent me. And this is the will of him who sent me, that I should lose nothing of hall that he has given me, but raise it up on the last day. For this is the will of my Father, that everyone who looks on the Son and believes in him should have eternal life, and I will raise him up on the last day.” -- John 6:32-40 (ESV)
“Truly, truly, I say to you, whoever believes has eternal life. I am the bread of life. Your fathers ate the manna in the wilderness, and they died. This is the bread that comes down from heaven, so that one may eat of it and not die. I am the living bread that came down from heaven. If anyone eats of this bread, he will live forever. And the bread that I will give for the life of the world is my flesh.”
The Jews then disputed among themselves, saying, “How can this man give us his flesh to eat?”
So Jesus said to them, “Truly, truly, I say to you, unless you eat the flesh of the Son of Man and drink his blood, you have no life in you. Whoever feeds on my flesh and drinks my blood has eternal life, and mI will raise him up on the last day. For my flesh is true food, and my blood is true drink. Whoever feeds on my flesh and drinks my blood abides in me, and I in him. As the living Father sent me, and I live because of the Father, so whoever feeds on me, he also will live because of me. This is the bread that came down from heaven, not like the bread the fathers ate, and died. Whoever feeds on this bread will live forever.” Jesus said these things in the synagogue, as he taught sat Capernaum.
-- John 6:47-51 (ESV)
On the last day of the feast, the great day, Jesus stood up and cried out, “If anyone thirsts, let him come to me and drink. Whoever believes in me, as the Scripture has said, ‘Out of his heart will flow rivers of living water.’”
Now this he said about the Spirit, whom those who believed in him were to receive, for as yet the Spirit had not been given, because Jesus was not yet glorified.
-- John 7:37-39 (ESV)
“This cup that is poured out for you is the new covenant in my blood.” -- Luke 22:20 (ESV)
Under the new covenant you need to:
- Examine yourself
- Repent from your sin
... so that you could enjoy eternal life
“I am the true vine, and my Father is the vinedresser. Every branch in me that does not bear fruit He takes away, and every branch that does bear fruit He prunes, that it may bear more fruit. Already you are clean because of the word that I have spoken to you. Abide in me, and I in you. As the branch cannot bear fruit by itself, unless it abides in the vine, neither can you, unless you abide in me. I am the vine; you are the branches. Whoever abides in me and I in him, he it is that bears much fruit, for apart from me you can do nothing. ... -- John 15:1-8 (ESV)
In other words, you become part of God's Son's body if you "abide in" (stay in a close relationship with) Jesus. The Greek word translated as "abide" in the English bible is "meinate" which means:
remain, stay, wait
If you cannot even "wait" for fellow believers, how can you "wait" for the "Lord until he comes" (1 Corinthians 11:26)?
Proclaim the Lord's death
This is an opportunity to explain the meaning of the death of the Christ to potential visitors or children:
For I received from the Lord what I also delivered to you, that the Lord Jesus on the night when he was betrayed:
- took bread, and when he had given thanks,
- he broke it [the bread], and said, “This is my body, which is for you. Do this in remembrance of me.”
- In the same way also he took the cup, after supper,
- saying, “This cup is the new covenant in my blood. Do this, as often as you drink it, in remembrance of me.”
For as often as you eat this bread and drink the cup, you proclaim the Lord’s death until he comes.
-- 1 Corinthians 11:23-26 (ESV)
The "Lord's death" would not make sense unless all visitors understand the Gospel of Jesus the Christ.
The word for "remembrance" in Greek is "anamnésis" which means:
a recalling, remembrance, memory
self-prompted recollection especially as a memorial
In other words, by participating in Communion, believers ought to testify to each other what the Lord's death meant to them like we do at a memorial service.
Serving each other
Now before the Feast of the Passover, when Jesus knew that his hour had come to depart out of this world to the Father, having loved his own who were in the world, he loved them to the end. During supper, when the devil had already put it into the heart of Judas Iscariot, Simon's son, to betray him, Jesus, knowing that the Father had given all things into his hands, and that he had come from God and was going back to God, rose from supper. He laid aside his outer garments, and taking a towel, tied it around his waist. Then he poured water into a basin and began to wash the disciples' feet and to wipe them with the towel that was wrapped around him. -- John 13:1-5 (ESV)
When he had washed their feet and put on his outer garments and resumed his place, he said to them, “Do you understand what I have done to you? You call me Teacher and Lord, and you are right, for so I am. If I then, your Lord and Teacher, have washed your feet, you also ought to wash one another's feet. For I have given you an example, that you also should do just as I have done to you. Truly, truly, I say to you, a servant is not greater than his master, nor is a messenger greater than the one who sent him. If you know these things, blessed are you if you do them.” -- John 13:12-17 (ESV)
“Truly, truly, I say to you, whoever receives the one I send receives me, and whoever receives me receives the one who sent me.” -- John 13:20 (ESV)
- Jesus and his disciples (Matthew 26:26-28, Luke 22:17-20, Mark 14:22-25)
- The first Jewish believers in Jerusalem (Acts 2:42)
- The Asian believers in Troas, who gathered on the first day of the week, at the "upper room" (possibly at someone's house) (Acts 20:7,11)