The book explores the dynamics of the spiritual domain, the worlds of the , souls and angels. Rabbi Kaplan explains that when properly understood the becomes an instruction manual for a very special type of meditation meant to strengthen concentration and to aid in the development of telekinetic and telepathic powers. Through the use of various signs, incantations, and divine names, initiates could also influence or alter natural events. This translation includes the meditation in five dimensions, the transition from to consciousness, the point of infinity, kabbalistic astrology, Ezekiel’s vision according to the , and the mystery of the 231 gates. Also included is a digest of all major commentaries on the text of the and a bibliography of many of the major kabbalistic works that discus it, as well as extensive notes regarding the various aspects of the translation. Rabbi Kaplan’s translation is based on the Gra version of the text, which is thought to eb the most authentic. Also included is the short version, the long version, and the Saadia version, making this volume the most complete work on the available in English.