"Now THAT is an excellent question. The timing element does seem to be all wrong, doesn't it?"
As I have commented before, the Scriptures give evidence that God preserves people in some way for special purposes. With Elijah, the Scripture is clear that he did not die, but was taken up into heaven -- whoever said that Elijah was in Hades has to contradict Scripture. We have the same phenomenon with Enoch. Orthodox tradition is that the two witnesses at the end of time, spoken of in the Apocalypse, will be Elijah and Enoch. They *then* will die, being martyred in the streets of Jerusalem.
Moses also was special. He died, and God did not allow anyone to be with him at his death or to bury him. Scripture says that God buried him. Then, in Jude, we have the account of St. Michael and Satan disputing over the body of Moses. Why dispute over a dead body? The implication to me is that God was going to resurrect him and take him to heaven, although I'm not sure that this is spelled out in Tradition.
(An aside: There is an apocryphal work called the Assumption of Moses -- I've not read it and I'm not sure it is translated or even still extant -- that some have said Jude is referring to. As with the Protoevangelion, I would be careful about going to that work, if you can find it, and saying that this work in its entirety reflects Orthodox tradition. There is a common source in Holy Tradition, but we cannot hang on the reliability of every passage of these written accounts the way we can with Scripture. If we could, they would *be* Scripture.)
Regardless, with Moses' death, something unusual was in the offing. Another possibility is that at the Transfiguration, Christ appeared out of time, and that Moses and Elijah were seen mystically in their post-resurrectional state. Again, this is me, not anything that I have read patristically.
The bottom line is that I don't think that it is accidental that the Scriptures just happen to have accounts of unusual circumstances surrounding the end of the earthly lives of the two men who appear with Christ at the Transfiguration.
"I've got one I also can't answer. If John the Baptist was, by Christ's account, in essence, the finest human to ever live, and if JTB is actually Elijah, then what were either or both of them doing in Hades at all?"
Christ does not say that John the Baptist was literally Elijah the Tishbite returned to earth. How could that be, since John the Baptist was conceived of Elizabeth and Zacarias? That would mean that Christianity believed in reincarnation. There is something in the patristic commentaries that, as I recall, even point out some ambiguity in Christ's statements that show that he is both saying that Elijah has come, and that he will come. I'll have to look it up.
When Elijah *the Tishbite* (as the LXX specifically says in Malachi) returns literally, it will not be by being reincarnated in another body and born of a woman. He will return from heaven with Enoch. Malachi refers simultaneously to St. John the Baptist (who is, so to speak, a 2nd Elijah) and to the literal return of *the* Elijah the Tishbite at the end of time, in his prophecy.
As another aside, I do not see why we would limit God by saying that only those mentioned in Scripture might be preserved from death or resurrected "prematurely." Those are just the ones we know about. Holy Tradition tells us that the Theotokos was probably taken up into heaven bodily after her death. Why Elijah, Enoch, and probably Moses -- and not her? Christ makes the ambiguous statement about St. John reported in the Gospel, saying to the other disciples "what is it to you if he doesn't die, but remain until I return." St. John spells out that Christ didn't say that he wouldn't die. But there are interesting implications to Christ's statement. I certainly wouldn't make assumptions about what God can and can't do, and Christ himself was telling us that we shouldn't.
I'll ping the others that you pinged, to see if they have further comments.
This is a tough one for me, as I do agree with you about the problem of reincarnation. Here are two passages of what Jesus does say, with the seemingly uncontradicted last sentence (in the second one) about His audience:
Matt. 11:13-15 : 13 For all the Prophets and the Law prophesied until John. 14 And if you are willing to accept it, he is the Elijah who was to come. 15 He who has ears, let him hear.
Matt. 17:11-13 : 11 Jesus replied, "To be sure, Elijah comes and will restore all things. 12 But I tell you, Elijah has already come, and they did not recognize him, but have done to him everything they wished. In the same way the Son of Man is going to suffer at their hands." 13 Then the disciples understood that he was talking to them about John the Baptist.
Jesus appears to compare the untimely deaths of both Himself and of John the Baptist, since "Elijah I" :) didn't die. However, OTOH, we have JTB's own denial:
John 1:21 : They asked him, "Then who are you? Are you Elijah?" He said, "I am not." "Are you the Prophet?" He answered, "No."
This one hurts my head. :)
When Elijah *the Tishbite* (as the LXX specifically says in Malachi) returns literally, it will not be by being reincarnated in another body and born of a woman. He will return from heaven with Enoch. Malachi refers simultaneously to St. John the Baptist (who is, so to speak, a 2nd Elijah) and to the literal return of *the* Elijah the Tishbite at the end of time, in his prophecy.
Then how are the statements of Jesus explained? Jesus is clearly referring to the prophecy in Malachi, and appears to be saying, in chapter 11, that JTB IS this Elijah. I can't explain it. :)