The title of Idel's 1988 historical and phenomenological analysis of Kabbalah's theoretical and practical genesis aptly indicates its thoroughgoing reevaluation of assumptions then current in Kabbalah scholarship, many of which can be credited to the commanding influence exercised by the authoritative works of Gershom Scholem dating to the mid-20th century. Idel presents Kabbalah as comprising two distinct streams: the mystical-ecstatic, wherein the devotee practices techniques for attaining a personal experience of unity with the divinity, and the theosophical-theurgical, which focuses upon the actively-intentional adherence to the Torah as a means of effecting positive reactions within the divine structure, and ultimately the maintenance of the cosmos. In terms of historical transmission, Idel refutes Scholem's attribution of certain Kabbalistic concepts to the influence of Gnosticism, as well as any probability that the emergence of Kabbalah per se in the late 12th century represented an innovative discontinuity. Rather, he demonstrates that the epistemological underpinnings of Kabbalah were already present in the earliest Rabbinic texts of late antiquity.
Despite an abundance of obscure historical personages and Hebrew theo-philosophical terminology, even non-specialist readers should have little difficulty following the essential arguments. Idel's interpretations of the evidence, both historical and theoretical, are supported by his closely-argued readings of copious primary sources; nevertheless, the text is far from dry, and retains an engaging authorial voice throughout. This book is well worth reading for anyone with a serious interest in Jewish intellectual history, or religious mysticism generally.