Why does God care what religion you are?

[mburbank]

In most religions, God demands that you believe in a very speciffic version of Him.

I can see God wanting you to follow a set of behavioral rules, as this might have a lot of impact on what happens on earth, but why is He so concerned about how you think of Him as long as you try to be good? Doesn't this lead to a lot of 'slaying the infidel'?

I could imagine a God heavily invested in your moral behavior, even to the point of actively punishing bad behavior and rewarding good, but I just can't think of a single reason God would concern Himself with what you called him, how and where you prayed, how you imgained him, etc.

I'm not throwing down a gauntlet here, I'm looking for thoughts on the matter from informed believers in speciffic faiths.