The Intellectual Journey of an Early Modern Kabbalist: An Analysis of Isaiah Horowitz’s Notebook, MS Oppenheim 268

Isaiah Horowitz (1565-1629) was a rabbi and kabbalist best known for his monumental work of ethical and kabbalistic literature, the Shnei Luhot ha Berit - a work which had a profound influence upon Ashkenazic Jewry in particular from its date of publication (Amsterdam, 1649) onwards. Notable themes of the work include the presentation of kabbalah as a theology of Judaism, the formulation of a proto orthodoxy several centuries before the term became popular and a pronounced focus on joy, passion and the role of individual self-actualisation in bringing the messiah. The Oppenheimer collection housed in the Bodleian library contains a notebook which Joseph Avivi discovered belonged to Horowitz as he composed his life`s work, written between approximately 1606 and 1621. Cryptic, terse and at times incomprehensible, in this paper I argue that this document provides essential evidence for the impact of Isaac Luria`s kabbalah on Horowitz`s thinking, and by comparing it to Horowitz`s later writings I sketch the trajectory of his intellectual journey. It also provides important evidence for how Horowitz developed a distinctive vision of pietism which was to have dramatic impact upon subsequent groups such as the Hasidic movement in the 18th Century. More broadly, this analysis shows how early modern intellectuals processed and applied new knowledge, and seeks to uncover the methodology behind rabbinic kabbalists of the 17th century as they tried to integrate new information and perspectives into their worldview. This manuscript opens an important and relatively unexplored window into how mystical writings by authors such as Luria and Moses Cordovero were incorporated and interpreted by later authors, and provides additional insight into the relationship between notebooks, printed texts and the development of Jewish thought in the 17th Century.