The Imam, the Divine Guide, is the central point around which the Shi'ite religion turns. The power of Shi'ism comes from the actions of the Imam. This title is reserved exclusively for the sucessors of the prophets in their mission. The author shows that from the beginning of Shi'ite Islam until the tenth century, the Imam was primarily a master of knowledge with supernatural powers, not a jurist theologian. The Imam is the threshold through which God and the creatures communicate. He is thus a cosmic necessity, the key and the center of the universal economy of the sacred.

The author...