Many theologians and commentators (and even mere readers of Scripture) have noticed a dynamic called "the already and not yet" of prophetic passages. That phrase is usually applied to Old Testament prophecies and their fulfillment in both the New Testament "church age" and in the still-to-come future age after Christ returns. But in a sense it also applies to prophecies that have been completely fulfilled in history like many about the first coming of the Messiah that are found in Isaiah, the book that I've been reading and studying for my time with the Lord in the last few months. And I also believe that the dynamic is true of the bulk of the prophecies in Revelation (I'll explain as we go).
I like to use the term multiple referents when referring to this dynamic (no pun intended:). What I mean is that a particular prophecy often refers to something that will occur in the near future (from when it was written) but then also speaks in a broader sense to things that will happen in the far future (from when it was written). Almost all scholars of any eschatological stripe recognize that this is happening with some prophecies at least, including dispensationalists who insist on a "literal" interpretation of prophecy but acknowledge that certain passages refer to both the church and a future Israel. A good example would be the New Covenant promises, which must apply to the church because several NT passages directly say that, but they also believe there is a future fulfillment in a Jewish millennial kingdom.
So why can't we all agree that there are multiple referents for many, if not all, biblical prophecies, both in the Old and New Testaments? It seems that this would provide some "reverse polarity" in our eschatological battles (to quote the late Neil Peart:) and allow us to be more open to one another's perspectives without throwing around pejorative labels like "allegorist" or "wooden literalist." For example, my dispensational and pre-millennial friends could be more open to the possibility that the events described in Revelation 6-19 could have been referring (at least initially) to the fall of the deicidal systems of Jerusalem and Rome, and I could be more open to a future conversion of Jews and other more "literal" fulfillments of Old Testament prophecies in the new heavens and earth.
The more I read and study biblical prophecy, the more I think that our experience at the consummation will be similar to what we do now with Old Testament predictions about the first coming of Christ. We say "Wow, that's amazingly accurate!" and realize that what it was saying became clear only after the events actually happened in history. (I have that experience with Revelation 6-19, by the way.) I think we'll be even more amazed when history comes to a close and we see all the ways many other prophecies have been fulfilled (though we see now "through a glass darkly"). And I think we'll see multiple referents for many, if not all, of those prophecies.
Here's an example that I just read about in my time with the Lord this morning. (I was reading Spurgeon's comments on the passage, so that's why the version quoted is KJV.)
In Isaiah 22 the prophet talks about events that will occur during his lifetime--he actually names the people he's talking about, like Shebna the scribe and Eliakim the son of Hilkiah (vv. 15 and 20). But when we read the description of Eliakim in particular, we can't help but see indications that he was a type of the Messiah who would come 700 years later, especially since some of the terminology used for him is found in other passages where Isaiah is clearly talking about Jesus (9:6-7, 16:5). Here's Isaiah 22:20-23...
"And it shall come to pass in that day, that I will call my servant Eliakim the son of Hilkiah: And I will clothe him with thy robe, and strengthen him with thy girdle, and I will commit thy government into his hand: and he shall be a father to the inhabitants of Jerusalem, and to the house of Judah. And the key of the house of David will I lay upon his shoulder; so he shall open, and none shall shut; and he shall shut, and none shall open."
The initial referent of that prophecy is a person and circumstances that were familiar to the readers, and the events predicted would soon come to pass in their world. (I believe this is like the predictions about Jerusalem and Rome in Revelation, where John says they "must shortly take place" "for the time is near.") But Eliakim is not the only ruler referred to in the passage--Jesus Christ is almost certainly a second referent of the prophecy. (And in my understanding of Revelation there can still be referents after the early centuries, because the dynamics described in the book take place in different ways throughout history, a la the historicist and idealist views, and even may at the consummation of history, a la the futurist view.)
Because of the multiple referents in biblical prophecies, it is completely legitimate for preachers and teachers to apply what Isaiah says about Shebna and Eliakim to us today, and I want to leave you with some of the tremendously insightful and encouraging thoughts Spurgeon shared about Isaiah 22. (That's the main purpose of all biblical eschatology, by the way--to change our lives now for the better.)
About the stubborn "nail" of Shebna being removed (Isa. 22:15-19), and the downfall of his glory, Spurgeon writes:
Whenever Jesus Christ comes into the heart, before he rides in state into the Castle of Mansoul, there is a battle, a strife, a struggle, a down-casting of the image of sin, and then a setting up of the cross in its place. All men, by nature, have some kind of righteousness. There is no man so vile but he still wraps himself up in his rags and cajoles himself into the belief that he has some degree of excellence, spiritual or moral. Before Christ can come into the heart, all this natural excellence must be torn to shreds; Every single stone of the wall upon which we have builded aforetime must come down, and the foundations must be utterly destroyed before we shall ever build aright and surely for eternity upon the cornerstone of Christ Jesus.
The tendency of human nature, as long as we are in this world, is to get something to rest upon in ourselves. We can hardly be indulged with the light of Jehovah’s countenance before we begin to make a confidence of it; and if our graces for a little while bud and bloom like seeming flowers, we very soon begin to compliment ourselves upon our imaginary goodness. Borrowed though every excellence be, we begin to be proud of it, and to forget too much that in him is all our salvation, and all confidence. This knocking down has to be persevered in, for the flesh lusteth against the Spirit; and yet as fast as we can, in our pride build up anything in which we can glory, the Lord sends a terrible blast of some kind or other against the wall, and sweeps it all down, that Jesus Christ may alone be exalted in our experience.
Then, after profoundly picturing the repentance we need for both salvation and sanctification, Spurgeon goes on to wonderfully describe saving and sanctifying faith and the promise of the gospel in verses 20-23 (the nail fastened in a sure place):
If God bids me lean my whole weight upon his Son, and I do so lean, and yet am not sustained, then is there a great mistake, not on my part only, but on the part of Infinite Wisdom. But we cannot suppose that. The Lord knew what he was doing when he appointed the Only Begotten to be the sinner’s pillar of strength, upon which he might lean. He knew that Jesus could not fail; that as God he was all-sufficient; that as perfect man he would not turn aside; that as a bleeding surety, having paid all the debt of our sin upon Calvary, he was able to save to the uttermost all them that come unto God by him.
I hope those words will be a blessing to you, both today and throughout whatever future God has planned for you!
[If you're curious about the different understandings of Revelation, you can listen to some teaching of mine here, here, and here.]