In history, Judaism, Christianity and Islam have been both partners and rivals. The well-known parable of the three rings argues in a beautiful paradox how the religion most beloved by the other two will turn out to be in possession of the true ring. This book collects a number of texts in which not just bilateral religious dialogues but the relations between one's own religion and the two others are documented. The texts translated and studied here date from the medieval period, both from the East and from the West. The shared knowledge of different religious traditions as testified to in some of these texts, may come as a surprise. Basic patterns of mutual understanding, pluralism, tolerance and dialogue-still relevant today-are drafted.