This challenging work describes in detail the development and history of the three major monotheistic faiths—Judaism, Christianity, and Islam—but also asks why they conflict with one other. Rather than uniting the believers, monotheism has played a crucial role in fostering a fractious society through the manifestation of three different, antagonistic religious systems with each religion claiming to represent God's will and viewing spiritual peace as possible only through victory over the others. This text shows how monotheism can become a unifying force for humanity, posing arguments that will intrigue psychologists, theologians, and general readers alike.