Hmm...That is a lot to think about.
This is going to seem strange but here is something that I think about. Religon teaches a possible life after death. They (most of them) also teach that a spirit lives on after death. Growing up I knew things that had happened to people (all of which were pinned on demons). Just because I don't necessarily believe that demons are messing with people doesn't mean that the unexplicable things happened (ex., things moving around). This makes me think that there is definitely a possibility of something unknown to us such as spirit beings or maybe some sort of existance after death. I have no idea what I think about it all but it certainly has lead to a lot of my "what ifs".
Not sure if I explained that well but I tried. I guess I think if it is possible that there is a conscious being other than us out there somewhere than maybe there is some chance that there is something to the whole what happens after death thing. This in turn makes me wonder about sin which possibly aids in determining what happens after death.
I really don't know if that all makes sense. In my mind it did but I guess I'll find out if anyone else understood. :)