Diana Lobel, Between Mysticism and Philosophy: Sufi Language of Religious Experience in Judah Ha-Levi's Kuzari, State University of New York Press, 2000.  

From the Publisher:

“A revealing study of this important medieval Jewish poet and his relation to Islamic thought.

Judah Ha-Levi (1075-1141), a medieval Jewish poet, mystic, and sophisticated critic of the rationalistic tradition in Judaism, is the focus of this ground-breaking study. Diana Lobel examines his influential philosophical dialogue, Sefer ha-Kuzari, written in Arabic and later translated into Hebrew, which broke religious and philosophical convention by infusing Sufi terms for religious experience with a new Jewish theological vision. Intellectually engaging, clear, and accessible, Between Mysticism and Philosophy is an indispensable resource for anyone interested in the intertwined worlds of Jewish and Islamic philosophy, religion, and culture.”

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