Communion is the name given to the act of meeting together to share bread and wine in remembrance of Christ’s sacrifice.
The meal was instituted in the evening before Christ died.
Matthew 26:26 And as they were eating, Jesus took bread, and blessed it, and brake it, and gave it to the disciples, and said, Take, eat; this is my body. 27 And he took the cup, and gave thanks, and gave it to them, saying, Drink ye all of it; 28 For this is my blood of the new testament, which is shed for many for the remission of sins.
Mark 14:22 And as they did eat, Jesus took bread, and blessed, and brake it, and gave to them, and said, Take, eat: this is my body. 23 And he took the cup, and when he had given thanks, he gave it to them: and they all drank of it. 24 And he said unto them, This is my blood of the new testament, which is shed for many.
Luke 22:19 And he took bread, and gave thanks, and brake it, and gave unto them, saying, This is my body which is given for you: this do in remembrance of me. 20 Likewise also the cup after supper, saying, This cup is the new testament in my blood, which is shed for you.
1 Corinthians 10:15 I speak as to wise men; judge ye what I say. 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? 17 For we being many are one bread, and one body: for we are all partakers of that one bread.
1 Corinthians 11:23 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: 24 And when he had given thanks, he brake it, and said, Take, eat: this is my body, which is broken for you: this do in remembrance of me. 25 After the same manner also he took the cup, when he had supped, saying, This cup is the new testament in my blood: this do ye, as oft as ye drink it, in remembrance of me. 26 For as often as ye eat this bread, and drink this cup, ye do shew the Lord’s death till he come. 27 Wherefore whosoever shall eat this bread, and drink this cup of the Lord, unworthily, shall be guilty of the body and blood of the Lord. 28 But let a man examine himself, and so let him eat of that bread, and drink of that cup. 29 For he that eateth and drinketh unworthily, eateth and drinketh damnation to himself, not discerning the Lord’s body. 30 For this cause many are weak and sickly among you, and many sleep. 31 For if we would judge ourselves, we should not be judged. 32 But when we are judged, we are chastened of the Lord, that we should not be condemned with the world. 33 Wherefore, my brethren, when ye come together to eat, tarry one for another. 34 And if any man hunger, let him eat at home; that ye come not together unto condemnation. And the rest will I set in order when I come.
Hebrews 10:25 Not forsaking the assembling of ourselves together, as the manner of some is; but exhorting one another: and so much the more, as ye see the day approaching.
Acts 2:42 And they continued stedfastly in the apostles’ doctrine and fellowship, and in breaking of bread, and in prayers… 46 And they, continuing daily with one accord in the temple, and breaking bread from house to house, did eat their meat with gladness and singleness of heart,
Acts 20:7 And upon the first day of the week, when the disciples came together to break bread, Paul preached unto them, ready to depart on the morrow; and continued his speech until midnight… 11 When he therefore was come up again, and had broken bread, and eaten, and talked a long while, even till break of day, so he departed.
The bread and wine in representing the body and blood of Jesus are also symbolic of the life that he led in obedience to his Father’s will.
John 6:53 Then Jesus said unto them, Verily, verily, I say unto you, Except ye eat the flesh of the Son of man, and drink his blood, ye have no life in you. 54 Whoso eateth my flesh, and drinketh my blood, hath eternal life; and I will raise him up at the last day.
1 John 2:6 He that saith he abideth in him ought himself also so to walk, even as he walked.
It is of no use eating bread and drinking wine in remembrance of Christ’s sacrifice if we are not living according to his commandments; thus the necessity of self-examination.
No day is specified for breaking bread, therefore it can be observed on any day. The early Christians found it convenient to meet on the first day of the week (Sunday) and this has become the tradition.
Communion should be restricted to baptised believers – members of the one body.
I hope you find this helpful.