This publication contains critical editions of the extant parts of two hitherto unknown theological works by the Buyid vizier al-Ṣāḥib b. ʿAbbād (d. 385/995), who is well known to have vigorously promoted the teaching of Muʿtazilī theology throughout Buyid territories and beyond. The manuscripts on which the edition is based come from Cairo Geniza store rooms. They consist of two manuscripts for each of the two texts—testimony to the impact of al-Ṣāḥib’s education policy on the contemporaneous Jewish community in Cairo. The longer treatise of al-Ṣāḥib of ca. 350/960, possibly his Kitāb Naḥl al-sabīl fī uṣūl al-dīn, appears to be the earliest Muʿtazilī work preserved among the Jewish community. The second, briefer treatise also contains a commentary by ʿAbd al-Jabbār al-Hamadānī (d. 415/1025).

Wilferd Madelung is Laudian Professor of Arabic, University of Oxford (emeritus).

Sabine Schmidtke is Professor of Islamic Intellectual History, Institute for Advanced Study, Princeton, NJ.

All interested in Jewish and Muslim intellectual history, specifically rational theology (kalām), during the Middle Ages, will find this edition valuable.