It was the “crucified Christ” that appeared in the “Upper Room” to Thomas. This shows that the Crucifixion and the Marriage Supper (Lord’s Supper) are United and the same.
Kind of hard to find an unbeliever like Thomas, an unregenerate man, as part of the Bride of Christ:
John 20:24-28 King James Version
24 But Thomas, one of the twelve, called Didymus, was not with them when Jesus came.
25 The other disciples therefore said unto him, We have seen the Lord. But he said unto them, Except I shall see in his hands the print of the nails, and put my finger into the print of the nails, and thrust my hand into his side, I will not believe.
26 And after eight days again his disciples were within, and Thomas with them: then came Jesus, the doors being shut, and stood in the midst, and said, Peace be unto you.
27 Then saith he to Thomas, Reach hither thy finger, and behold my hands; and reach hither thy hand, and thrust it into my side: and be not faithless, but believing.
28 And Thomas answered and said unto him, My Lord and my God.
Some confuse this...
John 20:21-23 King James Version
21 Then said Jesus to them again, Peace be unto you: as my Father hath sent me, even so send I you.
22 And when he had said this, he breathed on them, and saith unto them, Receive ye the Holy Ghost:
23 Whose soever sins ye remit, they are remitted unto them; and whose soever sins ye retain, they are retained.
With the Coming of the Comforter on Pentecost, but forget that the Spirit could not come if Christ did not return to Heaven:
John 16:7 King James Version
7 Nevertheless I tell you the truth; It is expedient for you that I go away: for if I go not away, the Comforter will not come unto you; but if I depart, I will send him unto you.
So we know Thomas is unregenerate because he has not received the Spirit, as well as the fact that he is denying Christ's Resurrection here. Christ proves it to Thomas by showing him that His body is literal, and can be touched and felt.
Christ breathing upon them does not nullify His Own teaching, and we can see that He tells them later that they will be "not many days" in Jerusalem before they receive the Spirit:
Acts 1:4-5 King James Version
4 And, being assembled together with them, commanded them that they should not depart from Jerusalem, but wait for the promise of the Father, which, saith he, ye have heard of me.
5 For John truly baptized with water; but ye shall be baptized with the Holy Ghost not many days hence.
For those that think the Baptism is an empowerment, or the filling of the Holy Ghost, Peter makes it clear it is not:
Acts 11:13-18 King James Version
13 And he shewed us how he had seen an angel in his house, which stood and said unto him, Send men to Joppa, and call for Simon, whose surname is Peter;
14 Who shall tell thee words, whereby thou and all thy house shall be saved.
15 And as I began to speak, the Holy Ghost fell on them, as on us at the beginning.
16 Then remembered I the word of the Lord, how that he said, John indeed baptized with water; but ye shall be baptized with the Holy Ghost.
17 Forasmuch then as God gave them the like gift as he did unto us, who believed on the Lord Jesus Christ; what was I, that I could withstand God?
18 When they heard these things, they held their peace, and glorified God, saying, Then hath God also to the Gentiles granted repentance unto life.
Peter makes it clear the Baptism with the Holy Ghost takes place at salvation, and in fact, is salvation.
Cornelius was saved at that time, received the Gift, and was granted repentance unto life when he was baptized with the holy Ghost.
So while I understand the correlation you are trying to make, it simply doesn't agree with Scripture. The Marriage Supper of the Lamb takes place at a specific point in time, and that we see Sunday as a special day, and "bread broken" in one of the events, that doesn't, in my view, justify a correlation to the Marriage Supper.
Continued...