Many scholars that study of religion and religious beliefs find that they affect behavioral patterns. Some of them suggest that this impact is morally wrong because religion and religious beliefs can cause aggression, conflicts, and wars. However, it seems that this topic is more complicated and complex. Here I show that religion and religious beliefs can affect mentioned above morally wrong patterns only in some particular cases. Usually they do not do it. Here I show an outline of philosophical historical (...) approach that was critically oriented against religion and that accused it about conflicts and wars. Then I briefly discuss two current scientific research approaches to the study of religion, cognitive and evolutionary. They falsify these critically oriented philosophers because they treat connection between religious beliefs and conflicts as random and necessary. The core idea of this paper assumes that religious beliefs do not affect aggression and wars directly. They can sometimes strengthen or weaken some biological mechanisms that then can be used to compete by conflicts or by not-violent inter-group competition. (shrink)