R. Judah Leib b. Baruch (fl. 1800), talmudic scholar and kabbalist, was the brother and disciple of R. Shneur Zalman of Lyady, the founder of the Habad movement, and preacher at Yanovichi. He recorded his brother's teachings in Hebrew, including his homilies which appeared later as Torah Or (Kopys, 1837). Some contributions by R. Judah are included in the siddur of R. Shneur Zalman. After his brother's death, he corrected R. Shneur Zalman's Shulhan Arukh and approved a new edition (ibid., 1822). There was a three-sided dispute among the latter's son, the "middle rabbi," and R. Aaron of Starosielce over who was to succeed R. Shneur Zalman. R. Judah, in a letter addressed to Aaron, supported his nephew. The "third rabbi," R. Menahem Mendel of Lubavich, included several contributions by R. Judah in his responsa.