Saadya, sometimes called al-Fayyumi from the section of Upper Egypt in which he was born, had a brilliant career as the most distinguished intellectual leader of Jewry in his age. He was twenty-three when he left his Egyptian home to play his part on the wider stage of Palestine, Syria, and Babylonia. By this time he had already composed the first known Hebrew dictionary and an important treatise refuting the views of Anan ben David, the founder of the rationalistic Karaite sect. In 921, the rabbis of Babylonia challenged the authority of the Palestinian rabbis to fix the Hebrew calendar. Saadya's defense of the position of the Babylonian rabbis was most effective; he was rewarded by appointment to the rabbinical academy at Sura in Babylonia; and a few years later, in 928, he was the first non-Babylonian ever to be named as the head (gaon) of the academy...