I watched United 93 a couple nights ago. It was a powerful movie. There is one scene in which several of the passengers in the rear of the plane are muttering the Lord's Prayer while the pilots are muttering Islamic prayers up front. It's powerful and disturbing. It's a caution.
I usually think it's easy to distinguish between good and bad religion, but I'm not so confident all the time. A popular technique is to measure it against what you know to be good or bad independent of that religion, but I think that only takes you so far. Sometimes what's good seems bad and what's bad seems good. And apparently I'm siding with terrorists here. (I don't really know much about it.) And that's the scary part (dangerous, if you prefer).
I've blogged before about such departures from what you might expect God to advocate. Perhaps one distinction is that when God does depart from what you would expect of Him, He only does it through prophets. So maybe Moses or Abraham or Joseph Smith or another prophet can give unexpected directions from God, but you can't kneel down and pray and determine that your own little boy is the Messiah and that you should therefore starve him (as one couple did in Utah several years ago).
But, there are those false prophets, so the responsibility comes right back at you. I remember being invited to hear a prophet speak on my mission. It was quite odd believing, as I do, that there are prophets, but that whoever the speaker in question was, he wasn't one of them and was therefore a false prophet. You judge a system of belief by your feelings, your feelings should be guided by what you know to be good and true already, and then specific problems in life are judged by consistency with that belief system. But feelings are unreliable, what is good and true can be excepted by God, and the complexity of life makes for frequent inconsistencies.
And yet, at the end of the day I feel fine about knowing the church is true, how I came to that knowledge, and the unexpected sacrifices that knowledge compels me to make.
It's a topic I don't really get. One of many. I think my mind makes it too broad and can't quite chew on all of it at once. I just cling to the little I know because it feels right enough to guide my everyday actions.