Fear Breeds Religion and Religion Breeds Fear
Fear, whether it is the fear of loss, the fear of rejection, the fear of punishment, or whatever, is at the center of a person's need to control. Fear prevents us from loving and appreciating our differences. Peace is found in the center of love. Love has to do with total acceptance of another person regardless of their beliefs or lifestyle. Loving others brings peace. How can it NOT?
There is a documentary called "Bowling for Columbine" in which Michael Moore discusses the very topic of fear. It is also his belief that fear is at the root of violence - especially in America where we have been afraid of terrorism, oppression, those different than us, since the very beginning. Fear is what encourages our society to fight wars and kill people; we want to gain control of a commodity or nation because we fear not having enough for ourselves.
It is in the nature of everyone to believe that they are right. Most people will staunchly defend their beliefs. Fear and violence comes into play when a group of people, who think they are right, form a religion with a prejudice toward others. You see this not only in religion but in white supremist groups and government leaders who have no regard for what their "subjects" want or need. These groups become a gang with a mob mentality who say they are doing "God's work" as a justification for behaving violently towards the people who don't believe as they do. I would hope that religion does affect our actions, but in a positive way—in a way that would encourage understanding and acceptance instead of judgment.