R. Isaac Izik ben Mordecai ha-Levi Epstein (c. 1780–1857) was a talmudist and kabbalist. R. Epstein, who had already written halakhic works in his youth, attached himself against the will of his grandfather to Habad Hasidism, and thenceforth devoted himself to the study of Kabbalah and Habad teaching, burning his previous halakhic writings. He felt that only R. Shneur Zalman of Lyady, whose favorite pupil he became, was capable of revealing the innermost secrets of the divine Law. R. Epstein served as rabbi of Gomel. In his old age he himself made his debut as a ẓaddik. In the handling of halakhic problems he took pains to write in an unpretentious and clear style. He left ten studies on Habad teaching including Ma'amar ha-Shiflut ve-ha-Simḥah (1864) and Ma'amar Yezi’at Mizrayim (1877); the others are in manuscript. He also wrote homilies for the weekly portions of the Law and the festivals, some of which were published with his Ma'amar Yeẓi'at Miẓrayim.