The Old Testament prophets (we could even include Moses here) were sometimes vague about future events: kingdom, Messiah. They were vague probably for a couple of reasons. Let me first give you an illustration that I heard from a professor of mine. It's sort of like being in an airplane, and when you're high above, when you're at max elevation, you know, you can hardly see anything, but as you descend you can start to make out, hey, that land, that's water. Then a little bit farther then it's that's a city, that's a building. And you keep going down, you're like, that's a car, that's a person. And then you finally make your way down so then you can see all the details. The earlier parts of the Old Testament are a lot like that. They see earth, they see the sea, they may even see a city. But then the latter parts, once you get into Daniel, you can start to see the cars and you can start to see the people. They aren't talking about two different things. It's the same thing that they're describing, it's just from different vantage points. The second part of the question is, how much did and really the most question here is how much did the Old Testament author know at that time? What we have to do is we have to look at their prophecies in light of the whole; that is, you have to look at all of the author's all of that particular author's writing. So, if you're looking in Deuteronomy, at the end of Deuteronomy he starts talking about eschatology, about Israel coming going into exile, coming out of exile. Well, you've got to look at some of the features of all of the Pentateuch to see if maybe he talks about similar things or maybe other pieces of the puzzle elsewhere so that you can combine that with these prophecies. So, maybe they knew more than what they were actually saying in that particular passage. All that to say is we've got to look at these events from the vantage point of it's going to get more detailed as it unfolds. But then also, even in the earlier parts of the Old Testament, we've got to look at the big chunks. You can't just look at just one particular chapter or one particular paragraph. You've got to look at that author's all of their writing. You've got to look at the whole Pentateuch. In other words you've got to figure out what does Genesis 3:15 have to do with the end of Deuteronomy? And once you start to put those pieces together, then you have, I think, a little bit better picture than what you thought you did.