Where did the idea of a single God come from in our perception? How have people's ideas about God changed? What features endowed Him with three world religions of monotheism - Judaism, Christianity and Islam? What influence did these three religions have on each other? The author created a real miracle: she covered the entire history of monotheism in one book - from Abraham to the present day, from ancient philosophy, medieval mysticism, the spiritual quest of the Renaissance and the Reformation up to the skepticism of the modern era.