Paul said the Lord’s supper is about discerning the body of Christ, not sin confession. Christ hadn’t been crucified yet. I believe Jesus was instituting the pattern to follow. He said to do it in remembrance of Him. A memorial service is for those who have died.
1 Corinthians 11:27-29
27So then, 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.
28Everyone ought to examine themselves before they eat of the bread and drink from the cup.
29For those who eat and drink
without discerning the body of Christ eat and drink judgment on themselves.
Luke 22:19
19And he took bread, gave thanks and broke it, and gave it to them, saying, “This is my body given for you;
do this in remembrance of me.”
Well, the Early Christians used to Confess their Sins before partaking of the Lord's Supper, as the Didache records: "
But every Lord's day gather yourselves together, and break bread, and give thanksgiving after having confessed your transgressions, that your
sacrifice may be pure. But let no one that is at variance with his fellow come together with you, until they be reconciled, that your
sacrifice may not be profaned. For this is that which was spoken by the Lord: In every place and time offer to me a pure
sacrifice; for I am a great King, says the Lord, and my name is wonderful among the nations." Taken from:
https://www.newadvent.org/fathers/0714.htmThe Scriptural reference in the latter part is to Mal 1:11.
But the issue is, when taking holy Communion, we should do it with faith in and love for Christ, right? Those people you mentioned in 1 Cor 11:27-29 did not do that, and thus ate and drank judgment upon themselves, and arguably same happened to Judas. Especially because the Gospel says:
"As soon as Judas took the bread, Satan entered into him." (Jn 13:27a)
The other disciples received the Lord's body and blood, but Judas received Satan. Imo, that is because, the other Apostles, though they were weak, loved the Lord. But Judas probably hated Him. Can you explain why someone would deliberately and knowingly hand over Christ to His enemies to be killed? What kind of thoughts must be going on in the heart of one doing that? The Word of God says:
"15Whosoever hateth his brother is a murderer: and ye know that no murderer hath eternal life abiding in him." (1 Jn 3:15). Wasn't Judas a murderer by killing Jesus just like Cain who killed his brother Abel?
Imo, he was. In theory, either he, or Hitler, or Stalin, or Margaret Sanger, or Ruth Ginsberg etc, could have said sorry to the Lord and tried to love Him again, but in practice, it is very rare, and hardly ever happens imo, if one hardens one's heart so as to deliberately kill. Hence, the Word of God says murderers do not have Eternal Life in them, giving the e.g. of Cain etc.
God Bless.