1. If Jesus left his glorified body behind to become a man, then perhaps so can Eve. In Philippians 2:7 it says that He emptied Himself by assuming the form of a slave. Angles can look like regular people. So, why not Eve? In fact, Satan might say "That really looks like Eve but there's no glory on her. It can't be her."
2. Can you use Adam and Eve's children instead of Adam and Eve? These, obviously, are the children never mentioned in the Bible and there isn't consensus on how many they did have. Adam lived a LONG time and I don't know how many children he had.
3. Be careful since it can sound New-Age-Ish if you're sharing people's souls.
1. What would Eve become if she left her glorified body? Do I make a special case out of her rather than simply stating she returned to Earth? Is she given a normal body for the duration of her second time on Earth? Where would she get that body? By being reborn? Also, what's the point from a story-telling perspective? It would also raise the question of whether Jesus too will shed his glorified body when he comes back. And let's not forget, Jesus's body was glorified while he was still on Earth. Therefore, glorified bodies can exist here.
2. The story wouldn't work unless I use Adam & Eve. After all, they are responsible for the disaster that befell mankind (naturally, Satan is also to blame).
3. These are totally unique circumstances, so Adam developing a multiple personality-like division within himself doesn't seem New Ageist depending on how I describe it. Since Connor never had a soul of his own, he technically doesn't exist. Or you could think of Connor as merely another of Adam's personas.
Christians believe that what makes us truly human is the soul. So who's to say a person with multiple personalities is an illness of the mind? Why not simply a reflection of multiple personalities in the soul, which arise for reasons we don't know? To me the most interesting cases of multiple personality disorder are the ones where each personality is a unique, fully functioning persona. Which of them is the real person, driven by the soul? And why are they so fully functional if only one of them is driven by the soul? Why is the latter personality sometimes indistinguishable from the others?
Or I can simply state that Connor/Adam are "like" someone with multiple personalities. The explanation for it will probably be the result of however it was that Adam was chosen as the soul of Connor. Perhaps it's the result of Adam asking God to allow him to return to Earth. It's not something that's normally done, so the result of doing so could be the "natural" development of a distinct personality within the soul for each time you are reborn. Who's to say I'm wrong about that? It's not normally done, so I'm free to make cacas up. :-)
Since Adam's soul is wounded, God may decide to allow it, knowing that the mission will heal his soul. But, of course, the price of that healing is the formation of a second persona, without whom the mission would fail. Or, knowing that Adam needed help, God could have been the one to give him the second persona. That would make this the only such event in history.
Technically, Connor is Adam. What's weird is my story planning has led me to the point where Adam is also the Antichrist. I no longer recall if my original idea for the story included Connor having Adam's soul. Probably not since I remember being concerned that I had no good ending for the trilogy. Some will definitely say what I came up with isn't a good ending either. :-)
CORRECTION: Turns out I did always plan for Connor to have Adam's soul. That's why Mother Palermo (the one possessed by legion in chapter 11) told him just before her death, "You are more than you know."