Saadia Gaon

Saʿadia ben Yosef Gaon or Said bin Yusuf al-Fayyumi (892–942) was a prominent rabbi, gaon, Jewish philosopher, and exegete who was active in the Abbasid Caliphate.

Saadia is the first important rabbinic figure to write extensively in Judeo-Arabic. Known for his works on Hebrew linguistics, Halakha, and Jewish philosophy, he was a student of the philosophical school known as "Jewish Kalam". In this capacity, his philosophical work entitled The Book of Beliefs and Opinions represents the first systematic attempt to integrate Jewish theology with components of ancient Greek philosophy. Saadia was also very active in opposition to Karaite Judaism in defense of Rabbinic Judaism.

Saadia was born in Dilāẓ in the Faiyum in Middle Egypt in 892. He immigrated to ancient Israel (in the Abbasid province of Bilad Al-Sham) in 915 at the age of 23, where he studied in Tiberias under the scholar Abu Kathir Yaḥya al-Katib (known as Eli ben Yehudah ha-Nazir in Hebrew), a Jewish mutakallim or theologian also mentioned by ibn Ḥazm. In 926, Saadia settled permanently in Lower Mesopotamia, known to Jews as "Babylonia", where he became a member of Sura Academy.

Saadia, in Sefer ha-Galui, stresses his Jewish lineage, claiming to belong to the noble family of Shelah, son of Judah, and counting among his ancestors Hanina ben Dosa, the famous ascetic of the first century. Saadia expressed this claim by calling his son Dosa; this son later served as gaon of Sura Academy from 1012–1018. Regarding Joseph, Saadia's father, a statement of the Palestinian gaon Aaron ben Meïr has been preserved saying that he was compelled to leave Egypt and died in Jaffa, probably during Saadia's prolonged residence in the Holy Land.

The usual nisba al-Fayyumi refers to Saadia's native place, the Fayyum, which is located in Middle Egypt; in Hebrew, it is often given as Pitomi, derived from a contemporary identification of Fayum with the Biblical Pithom, an identification found in Saadia's works.

At the age of 20, Saadia began composing his first great work, the Hebrew dictionary called the Agron. At 23, he composed a polemic against the followers of Anan ben David, particularly Solomon ben Yeruham, thus beginning the activity which was to prove important in opposition to Karaite Judaism in defense of Rabbinic Judaism. In the same year, he left Egypt and moved to Palestine.

In 921, Saadia triumphed over Gaon Aaron ben Meïr over the latter's introduction of a new triennial cycle of Torah reading that also changed the dates of Passover and Rosh Hashanah. Later, one of Saadia's chief disputants was the Karaite by the name of Abu al-Surri ben Zuṭa, who is referred to by Abraham ibn Ezra, in his commentary on Exodus 21:24 and Leviticus 23:15).

In the year 928, at the age of thirty-six (variant: forty-six), David ben Zakkai, the Exilarch or head of Babylonian Jewry, petitioned Saadia to assume the honorary title of gaon, where he was appointed that same year the Gaon of Sura Academy at Mata Mehasya, a position which he held for 14 years until his death.