Why do religious militants think their actions are right or righteous? What keeps me from acting like them? Why do some religious persons act on their beliefs in charitable, inspiring and deeply humane ways? Is secularism the solution to religious violence, or is it part of the problem? This Element explores the vexed issue of violence done in the name of God, looking at the topic through the lens of peace and conflict studies, religious studies and historical studies. The beliefs of various communities, religious and secular, are explored, looking at how convictions inhibit and enable violence. This Element aims to foster a deeper and more nuanced understanding of the promises and perils of religion so that readers can better respond to a world filled with violence.