This book explores the phenomenon of Saturnism, namely the belief that the planet Saturn, as described by ancient astrology, influenced Jews, reverberating into Jewish life. Taking into consideration the astrological aspects of Judaism, Moshe Idel demonstrates that they were instrumental in the conviction that Sabbatei Tzevei, the mid-17th-century messianic figure in Rabbinic Judaism, was indeed the Messiah. Offering a new approach to the study of this mass-movement known as Sabbateanism, Idel also explores the possible impact of astrology on the understanding of Sabbath as related to sorcery and thus to the concept of the encounter of witches in the late 14th and early 15th century. The book further analyzes aspects of 20th-century scholarship and thought influenced by Saturnism, particularly lingering themes in the works of Gershom Scholem and seminal figure Walter Benjamin.

Moshe Idel is Max Cooper Professor of Jewish Thought at the Hebrew University of Jerusalem, Israel, and Senior Research Fellow at the Shalom Hartman Institute, Israel. He is an expert in Kabbalah and has been a recipient of the prestigious Israel Prize for excellence in the field of Jewish philosophy.