Shawn Henderson wrote:
So, does he save the world, or something like that?
Oh no! Not even close. As my 
"World Endangerment" thread somewhat mentions, I'm not the biggest fan of the tendency in Fantasy and Sci-Fi (and even action stories to some degree) to rely on such large-scale conflict. The conflict in this story isn't going to be so grand as that; much smaller scale.
Shawn Henderson wrote:
It would be cool to not really explain it, and let the reader figure it out, although it might be irritating to never really know.
Actually, my thought is that the character never knows, so why should the reader? I think that if the character's non-questioning acceptance is portrayed well enough then most readers will probably be ok with that. Especially as the Christian aspect comes more into play there can be the idea that since God's in control, obviously this is something he allowed/caused. Dekker fans who've read 
Blink will remember that he takes a similar approach to explaining the protagonist's ability to see multiple possible futures. The story focuses more on his fight for survival and such because he doesn't have time to stop and wonder how it is that he's able to see these things. I plan on the same idea only different because I'm coming into the story long after Nocturnal has discovered this ability and stopped asking for lack of answers. I would start off slow enough for readers to get a feel for him and his world and then the action and conflict would move the story along to a point that the reader won't have time to ask "how is this possible?" That's my thought at least.