רבינו נסים

Rav Nissim ben Yaakov ibn Shahin (c. 4750/990–4822/1062), known to the generations as Rabbeinu Nissim Gaon, was rosh yeshivat Kairouan and the rebbi of the Rif. He was born in Kairouan, in today’s Tunisia, to Rav Yaakov ben Nissim, head of the city’s yeshiva; when his father was niftar in 4766/1006 the son was only sixteen, and the post passed to Rabbeinu Chushiel, father of Rabbeinu Chananel, under whom Rav Nissim then learned at Rabbeinu Chananel’s side. After Rabbeinu Chushiel’s passing he was raised to rosh yeshiva. He was never a gaon of the yeshivot of Bavel, but the title clung to him in honor of the yeshiva he led, the greatest of its day outside Bavel; the roshei yeshivot of Bavel themselves crowned him Rosh bei Rabbanan.

He stood in letters with Rav Hai Gaon and with Rav Shmuel HaNagid, and through these ties helped carry the Torah of the geonim of Bavel over to Sefarad. In 4809/1049 his only daughter married Rav Yehosef, son of Rav Shmuel HaNagid, and during a long stay in Granada for the wedding he taught gemara together with Rav Yehosef, who was also his talmid; his greatest talmid was Rav Yitzchak Alfasi, the Rif. When Kairouan was plundered and laid waste in the raids of 4817/1057, he moved to Mahdia, where he was niftar in 4822/1062.

His name lives in the Sefer HaMafteach — the key to the locks of the Talmud — which opens the sugyot the gemara cites only in passing, tracing their sources in the Tosefta, the Mechilta, the Sifra and Sifrei, and the Talmud Yerushalmi, and joining peirush to reference; it is printed on the daf of the Vilna Shas for several masechtot. His Megillat Setarim, a private notebook of piskei halacha, peirushim, and midrashim, was put out by his talmidim after his passing, and fragments found in the Cairo Geniza were published in our own day by Rav Yosef Kapach. His Chibur Yafeh MeHaYeshuah, some sixty stories of salvation drawn from Chazal, was written in Arabic to comfort his father-in-law Dunash on the loss of a son, and was first printed in Ferrara in 5317/1557. Other works — a siddur, a peirush on the Torah, a sefer on the mitzvot, and Hilchot Lulav — were lost, and survive in the quotations of later chachamim from Sefarad to Ashkenaz, Provence, Mitzrayim, and Eretz Yisrael. He was also a poet: Rav Shmuel HaNagid, himself among the great poets of Sefarad, wrote that Rav Nissim’s poems surpassed his own.