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Judah ben Isaac


JUDAH BEN ISAAC (Judah Sir Leon of Paris ; also called Gur Aryeh ("lion's whelp") or Aryeh , after Genesis 49:9 (Or Zaru'a, pt. 1 no. 17; Tosefot Yeshanim to Yoma 8a); 1166–1224), French tosafist. Judah headed the Paris bet ha-midrash, which was apparently reopened on the return of Jews after the expulsion of 1192. He studied many years under his teacher *Isaac b. Samuel of Dampierre who was his relative, together with his teacher's son Elhanan. Judah was numbered among the most distinguished pupils of Isaac, in whose presence he wrote tosafot to various tractates and whose rulings and responsa he collected (Assaf, in A. Marx Jubilee Volume (Heb., 1950), 11). Much of Judah's teaching is based upon that of his teacher Isaac which he incorporated into his own works (as did Isaac's other pupils), particularly into his tosafot.

Of his teachings there remain only his tosafot to the tractates Berakhot (first edition in Berakhah Meshulleshet, 1863; a supplement to pages 2a–8b was published by Sachs in: Sinai, 37 (1955) 87–105), and a new edition by N. Sachs collated with additional manuscripts began to appear in Jerusalem in 1969 under the title Ginzei Rishonim; Shitat ha-Kadmonim (ed. M.J. Blau), Avodah Zarah (1969), and a fragment of Nedarim (J.N. Epstein, Perushei R. Yehudah Ben Natan, in: Musaf le-Tarbiz, 3 (1933) 171–80). Although this fragment is attributed in the manuscript (Montefiore, see Kohelet Shelomo, Catalog… A.J. Halberstam, (1890) 58 no. 323) to Judah b. Nathan, Epstein proved that it was really by Judah b. Isaac. Many of his statements can be detected in the standard tosafot printed with the Talmud, particularly the Tosafot Yeshanim to the tractate Yoma, which are an adaptation by his pupil *Moses of Coucy (Urbach, Tosafot, 394), Megillah (ibid., 483f.) and Bava Kamma (ibid., 275). It is clear that he wrote tosafot to other tractates since he mentions them in the aforementioned works, where he alludes to his commentaries on 12 additional tractates: Shabbat, Pesaḥim, Beẓah, Rosh Ha-Shanah, Sukkah, Yevamot, Ketubbot, Kiddushin, Bava Kamma, Bava Batra, Ḥullin, and Niddah (ibid., 273 and n. 67). Those tosafot were known and used by scholars even at a later date, for instance by his pupils Moses of Coucy and *Isaac Or Zaru'a of Vienna, the latter's pupil Meir of Rothenburg, and even later by Aaron ha-Kohen in the Orḥot Ḥayyim and by Joseph Colon (ibid., and n. 68, p. 274 and n. 72). In addition there are references to other tosafot compiled by him on Eruvin, Yoma, Ta'anit, Nedarim, Bava Meẓia, and Shevu'ot (ibid., 274 and n. 73, 74). To these may be added references of his tosafot Mo'ed Katan (commentary of Talmid R. Jehiel of Paris to mk, 14b (in: Kitvei Makhon Harry Fischel (1937) and the Mordekhai (mk, no. 862), to Gittin (ibid., n. 73), and to Zevaḥim (Tos. Ri to Av. Zar. 51). Great scholars of France and Germany of the following generation, such as Jehiel of Paris, Moses of Coucy, Isaac Or Zaru'a of Vienna, and others, were his pupils (Isaac b. Abraham was not his pupil as stated by Ḥ.J. Michael), and they faithfully transmitted his decisions and customs in their works. Only a few of his responsa have survived. Judah also apparently occupied himself with the masorah and there is report of a Sefer Rabbenu Judah of Paris (G. De Rossi, Catalogue… Parma, no. 721). Judah has been erroneously confused at times with Judah he-Ḥasid (b. Samuel) and this error still persists, very likely because Judah was also occasionally referred to as "He-Ḥasid" ("the pious"; see Michael Or, no. 999).


H. Gross, in: Magazin, 4 (1877), 173–87; 5 (1878), 179–83; Gross, Gal Jud, 519–24; J.N. Epstein, in: Tarbiz, 4 (1932/33), 179–81; Urbach, Tosafot, 267–76.

[Shlomoh Zalman Havlin]

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