The Flowering of the Geonic Age and the Sheiltot of Rav Achai

After the Talmud was completed and the brief age of the Savoraim passed, leadership of the Jewish people moved to the heads of the two Babylonian academies, Sura and Pumbedita. They were called Geonim. The Baghdad caliphate had united lands from Spain to India under one rule, and for the first time Jewish communities across the world were linked by a single network of roads and post—and the Geonim used it.

Twice a year, in Adar and Elul, thousands of students gathered for the kallah, a public assembly studying a tractate assigned in advance. Letters arrived from everywhere: how to reckon the calendar where the new moon cannot be seen, whether prayers may be written down, what to do with an impossible vow. The answers—responsa—travelled back by caravan, and from this correspondence grew the practical halakhah of the entire diaspora.

Around 4510 Rav Achai of Shabcha, passed over for the office of Gaon, left for the Land of Israel and wrote the Sheiltot—the first independent book composed after the Talmud was sealed. It follows the weekly Torah portions: each opens with a legal question growing out of a verse, followed by a sermon on the commandment's moral meaning. Halakhot Pesukot, Halakhot Gedolot and the prayer book of Rav Amram Gaon followed.