Defender of the Faithful explores the life and thought of Levi Yitshak of Berdychiv (1740-1809), one of the most fascinating and colorful Hasidic leaders of his time. This is an intellectual and religious biography, a reading of the development of his thought and career. Featuring examples of Levi Yitshak's extraordinary texts alongside insightful analysis by scholar and theologian Arthur Green, Defender of the Faithful is a compelling study of both Levi Yitshak's theology and broader philosophy.