When we take religion too seriously, how often can it lead to unreasonable fear of others?

Religion sadly can make enemies (lot's of other things can to.) Catholics burned witches at the stake or simply killed them because they were scared of them. Witches never did anything wrong. (I know because I am a wiccan and it is simalar to witch) Satanists are thought to be mean people because of their belief but someone I know met a satanist and he was actually quite nice. Catcholics and Christians thought that they were the only religion that was correct and all of the others were stupid or wrong. To sum it up it leads to fear and hate of others quite often when those people are really serious about their eligion.