Hi Isa,
Maybe you can explain to me why some seem to place such importance on how early the two passages were linked. What difference does it make? The validity of the papacy is not dependent upon some sort of link being established between those two passages.
As has been explained so many times on the forum, the Isaiah passage is not seen as a prophecy of the papacy. One might consider it a “type” - keeping in mind that types are not the same in every detail when they are fulfilled. It may be just us non-professional Bible enthusiasts that enjoy connecting the two with typology! I know I did when I first read that section in Isaiah. I think Protestants would also if they didn’t have this built in resistance to anything that might seem to support the papal office Jesus established in His Church.
Usually the way I’ve seen the connection used in exegesis, is to show that the Jews were familiar with the office of the keys. When Our Lord gives Peter the keys of the kingdom in Matthew 16, Peter knows what Jesus is talking about and so do the other eleven. So did all the other Jews who heard the apostles when they related that event.
Nita