Hai Gaon (939-1038) was the last gaon, or leader of a Babylonian Talmudical academy, of Pumbedita, in what is now Iraq.
He received his Talmudic education from his father, Sherira, and served together with him as gaon until Sherira’s death in 998. Hai continued as gaon until his own death in 1038.
Hai’s chief claim to recognition rests on his more than 800 responsa, in which he gave decisions affecting the social and religious life of Jews in the Diaspora. Responding to questions submitted from Jews in Germany, France, Spain, Turkey, North Africa, India and Ethiopia, he addressed civil law, especially the laws concerning women, and laws concerning Jewish rituals and holidays. Many of his responsa are believed to have been written in Arabic; while many were cited by later scholars, only a few of them have been preserved
In one responsum, Hai was “among the earliest Jewish thinkers to discuss” questions of free will, according to Rabbi Louis Jacobs’ The Jewish Religion.
Hai codified various branches of Talmudic law, writing treatises on purchases, mortgages, oaths. He also wrote numerous commentaries on the Mishnah and compiled a dictionary of difficult words in the Bible, its Aramaic translations and Talmud.
Some piyyuṭim (liturgical poems) are attributed to him, including one that is part of the Sephardic Kol Nidre prayer service. Hai was not only a master of Hebrew lore, but was also familiar with Muslim texts, Greek philosophy and Christian writings.
Adapted from the Jewish Encyclopedia.
Pronounced: TALL-mud, Origin: Hebrew, the set of teachings and commentaries on the Torah that form the basis for Jewish law. Comprised of the Mishnah and the Gemara, it contains the opinions of thousands of rabbis from different periods in Jewish history.
Pronounced: tuh-FILL-in (short i in both fill and in), Origin: Hebrew, phylacteries. These are the small boxes containing the words of the Shema that are traditionally wrapped around one’s head and arm during morning prayers.
Pronounced: MISH-nuh, Origin: Hebrew, code of Jewish law compiled in the first centuries of the Common Era. Together with the Gemara, it makes up the Talmud.