Halachot Gedolot

Halachoth Gedoloth (lit. great halachoth) is a work on Jewish law dating from the Geonic period. It exists in several different recension, and there are sharply divergent views on its authorship, though the dominant opinion attributes it to Simeon Kayyara.

Kayyara's chief work is believed by some to be the Halakhot Gedolot (הלכות גדולות) whereas Moses ben Jacob of Coucy ("the Semag") wrote that it was in fact composed by Rav Yehudai Gaon.

Based on anachronistic discrepancies, the Semag's opinion that it was Rav Yehudai Gaon who composed the work Halachoth Gedoloth was thought to be an error. Rabbi David Gans may have been the first to suggest that the Semag, in referring to "Rav Yehudai" as the author, was actually alluding to Rav Yehudai Hakohen ben Ahunai, Gaon of the Sura Academy (served 4519 - 4524 of the Hebrew calendar)

As to the time of its composition, all the older authorities are silent. Abraham ibn Daud alone has an allusion to this problem, which has caused much perplexity. According to him (Sefer ha-Kabbalah, in M. J. C. i. 63), "Simeon Kayyara wrote his work in the year 741, and after him lived Yehudai Gaon, author of the Halakhot Pesukot, which he compiled from Simeon's Halakhot Gedolot." This statement cannot be relied upon, as Simeon Kayyara in fact lived in the century following Yehudai Gaon; and Halevy is of the opinion that the names were inadvertently switched, though this reading creates as many problems as it solves. The Ramban in his preface to Sefer Ha-Mitzvot says in passing that Simeon, not Yehudai, was the author of Hilchot Gedolot.

Many ancient authorities, like the Geonim Sherira and Hai ben Sherira, and others, support Kayyara's authorship; and according to A. Epstein, there can be no doubt that Simeon Kayyara wrote the Halakhot Gedolot. It would also seem from the statements of these authorities that Simeon Kayyara's chief sources were the She'eltot of Achai Gaon and the Halakhot Pesukot of Yehudai Gaon.

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