רב מבשר כהנא גאון

Rav Mevasser HaKohen (Kahana) ben Kimoi Gaon (gaon 4677/917–4682/922) headed the yeshiva of Pumbedita, the third of his family to sit at its head. His father was Rav Kimoi ben Achai, rosh yeshivat Pumbedita in the years 896–905, and his father’s father was Rav Acha Kahana ben Mar Rav, gaon of Pumbedita in 858.

When Rav Yehuda bar Mar Shmuel was niftar in 917, a dispute broke out over who would follow him. The chachamim of the yeshiva appointed Rav Mevasser as gaon, but he did not accept the authority of the Reish Galuta, David ben Zakkai, who answered by appointing Rav Kohen Tzedek ben Yosef. Standing at Rav Mevasser’s side were the gaon of Eretz Yisrael, Rav Aharon ben Meir, and the magnate Aharon ben Amram. According to Rav Sherira Gaon the machloket ran some five years, until a compromise was reached in 921/922 through the mediation of Nissi Naharwani: the two chachamim would each head a yeshiva in Pumbedita, side by side. The choicest of the chachamim sat in the yeshiva of Rav Mevasser, and only after his passing did all of them recognize the geonut of Rav Kohen Tzedek.

Rav Mevasser gave semichah to Rav Aharon HaKohen ben Yosef — Khalaf ibn Sargado — who became gaon of Pumbedita several generations later. Brought in his name is the teaching that Shimshon was punished for taking his own life, for all that he took great vengeance thereby on the Pelishtim (Philistines).