You can abuse almost everything. Also religion. In most religions people try to be peaceful and not to hurt anyone. Thats the point of religion. But its also true that some fanatics just pick out some phrases and use them for doing horrible things. But this is wrong and hypocritic. You can even abuse SALT to kill someone. Does that mean that salt is generally something bad and called poison? Are your knifes in the kitchen weapons or have they been made to be a helpful tool? Same goes for religion. Its a guide for a peaceful living together but once people start to think "they are better then others" the problem beginns. What you call "motive" is actually abuse of something good. So the bad people who do the bad things because it says so in their beliefs or book are misguided.