So, I am trying not to go too far into the literary connections between Revelation and other parts of Scripture but if I do, I try to bring out the theological implications first.
Anyway, I am currently working through the 7 Churches of Asia and arriving at Philadelphia, I noticed language very similar to that of Paul’s.
Compare Revelation 3.7-13 and 1 Co 11.27-32. Go ahead. I’ll wait.
Notice that Christ is the setting the table/open door. Compare 1 Corinthians 11.26 and Revelation 3.11. Compare as well the promise of Christ in 3.10 with Paul’s hope for the Eucharist — 1 Corinthians 11.28–32.
There is also some language here drawn from Isaiah 22.22, perhaps by way of Scott Hahn’s interpretation of Matthew 16.18.
Anyway, rather than the open door of John’s vision in Revelation 4, this is (and maybe there isn’t much difference) the Eucharistic table where Christ is presiding.