Isaac ben Judah of Mainz
ISAAC BEN JUDAH OF MAINZ
ISAAC BEN JUDAH OF MAINZ (11th century), German scholar; teacher of *Rashi. Practically no biographical details are known of him or his family. The description given by J.N. Epstein (see bibliography) of the characteristics of the yeshivah of Mainz during the period that Isaac was its head, and the manner in which it differed from the contemporary yeshivah of Worms, has been rejected by Aptowitzer (see bibliography). Isaac was head of the famous yeshivah in Mainz founded by his teacher *Gershom b. Judah, to whom he was apparently related, as he was to Rashi. He seems to have come from France (Zedekiah b. Abraham ha-Rofe, Shibbolei ha-Leket ed. by Buber (1886). 66 no. 93). He was also a pupil of *Eliezer ha-Gadol of Metz who was also one of the heads of the Mainz yeshivah. In addition to Rashi, he numbered Eliakim b. Meshullam among his distinguished pupils. Eliakim refers to him as Moreh Ẓedek ("the righteous teacher") whenever he mentions him in his commentary to Yoma and Rashi uses the same title on Yoma 16b and in his responsa. According to Abraham Epstein, the commentary attributed to Rabbenu Gershom in the Romm (Vilna) editions of the Talmud to the tractates Menaḥot, Bekhorot, Arakhin, Temurah, Keritot, Me'ilah, Tamid, Ḥullin, Ta'anit, and Bava Batra was compiled in Isaac's bet midrash. Eight of his responsa are included in the Teshuvot Ḥakhmei Ẓarefat ve-Loter (1881), and in the introduction to this work J. Mueller gives a list of 17 of his responsa and novellae which are scattered throughout the literature. I. Elfenbein's edition of Rashi's responsa (1943) contains 38 of Isaac's, mainly directed to Rashi.
E.M. Lipschuetz, R. Shelomo Yiẓḥaki (1912), 18f., 56f.; Epstein, in: Festschrift… M. Steinschneider (1896), 115–43; S. Buber (ed.), Sefer ha-Orah, 1 (1905), introd. 15–6; idem. (ed.) Zedekiah b. Abraham ha-Rofe, Shibbolei ha-Leket (1886), introd. 713; J. Mueller (ed.), Teshuvot Ḥakhmei Ẓarefat ve-Loter (1881), introd. 23–5; N. Epstein, in: Tarbiz, 4 (1932/33), 167–78; V. Aptowitzer, Mavo le-Sefer Ravyah (1938), 260, 296f., 311, 371f., 406f.; S. Hurwitz (ed.), Maḥzor Vitry (19232), introd. 33–6; D. Genachowski (ed.), Perush R. Elyakim le-Massekhet Yoma (1964), 12f.; I. Elfenbein (ed.), Teshuvot Rashi (1943), introd. and index 403; S. Eidelberg (ed.), Teshuvot R. Gershom Me'or ha-Golah (1956), introd. 26–33.
[Shlomoh Zalman Havlin]