Rabbi Yoel Kahn served as the principal redactor and editor of the teachings of the late Lubavitcher Rebbe, Rabbi Menachem M. Schneerson, for more than forty years. He was the author of the Encyclopedia of Habad Mystical Thought (Sefer haErchim Habad). The Senior Mentor and Instructor in Hasidic Thought at the Central Lubavitch Yeshiva in the Crown Heights section of Brooklyn, NY, he was renowned as the most authoritative internal scholar and exponent of Habad Mystical thought.