Kohen-Ẓedek Bar Ivomai
KOHEN-ẒEDEK BAR IVOMAI
KOHEN-ẒEDEK BAR IVOMAI (or Ikhumai ; 9th century), gaon of Sura from 838–48, succeeding R. Mesharshiya (or Moshe) Kahana after an interregnum of two years. Kohen-Ẓedek's responsa, usually in Hebrew (rather than the Aramaic common to most of the geonim before him) and couched in succinct terms, encompass all aspects of halakhah, particularly laws of blessings and texts of the liturgy. He apparently devoted a whole work to the Passover seder. It is assumed that Kohen-Ẓedek was the first (even before *Natronai b. Hilai) to compose a prayer book. He was very careful not to force upon communities who turned to him for advice the customs which prevailed in the Babylonian academies.
Abramson, Merkazim, 14; H. Tykoczynski, Takanot Ha-Geonim (1959), passim; M. Havazelet, Ha-Rambam ve-ha-Geonim (1967), 162; Baron, Social2, 5 (1957), 30; 6 (1958), 446; Weiss, Dor, 4 (19044), 38.