I think you've just created a three-sided argument.

I hope not, it wasn't my intention. I actually agree quite a bit with m6400, it is clear that we are coming from very similar points of view. The argument he's making about ethics being evidence for God is a good one, but it's difficult to encompass the whole if it in a forum of this kind. This line of reasoning is very clearly put forth in C.S. Lewis's Mere Christianity, but he takes several chapters to develop it.

That being said, there are all sorts of debatable issues within Christianity, but there are a few "non-negotiables", the heart of which is the Gospel: Jesus dies for our sins. I don't believe that evolution or science should be allowed to serve as a stumbling block to seekers when the real question is about sin, not science.

Moving on then,

So if you have a ``sin problem'', that would mean that you're hurting either yourself or someone else. Why does that necessarily have to have any relationship to God?

"Sin" means to "miss the mark." We are not living as the beings we were created to be when we sin. No matter whom a sin is against, ultimately God is aggrieved because we are not behaving in the perfect way we were created to operate.

There's no reason to believe that those sorts of ethics and morals have been inserted into us either through divine intervention or training.

I believe that these morals have been inserted into us by divine intervention, but I don't have any scientific proof of that. As mentioned above, C.S. Lewis has a very compelling philosophical argument for this idea.

All of this course this has no meaning if there is no God, or even if there is a God but he doesn't particularly care how we turn out. I fully recognize that the concept of "sin" is a religious one; in fact I believe that if there is no God or ultimate culmination of the effects of humanity, that there can be no real concept of "right" or "wrong".

This leaves only the ``no other gods/believe in me'' part. This has only internal logic. It means nothing if there is no God, and if you believe that there is a God, it's pretty self-fulfilling.

I'm not sure I quite understand what you mean by "internal logic" so you may need to rephrase, however what it comes down to is this: if Christianity is right, "sin" has consequence and must be addressed. If it is not, there is no such thing as "sin" (or if there is, it is determined by another "true" religion).

If the Christian concept of sin is true, there are consequences whether it can be proven or not. Christians believe that if people die without their sin problem being addressed, then they are eternally separated from God, the one who can love them perfectly as they were designed to be loved for all eternity. In effect, it is taking a "godless" state that is lived in now and making it permenant. Permenance for the person who has trusted Christ as savior is the same: it makes the current state of the Christian eternal, spending eternity worshiping and adoring a Creator who loves him or her perfectly. I say all of this because Christianity doesn't claim that sin is bad for sin's sake. It is bad because of the effects it produces in our lives and the ungodly state in which it leaves us.

I feel like I've glossed over something here. Please tell me what I've missed.

Actually I'm sort of feeling similar about how I've responded to your post, so maybe when should both clarify a bit.