Al-Ash'ari was born in Basra,^[6] Iraq, and was a descendant of the famous companion of Muhammad, Abu Musa al-Ashari.^[7] As a young man he studied under al-Jubba'i, a renowned teacher of Muʿtazilite theology and philosophy.^[8] He remained a Muʿtazalite until his fortieth year and he abandoned al-Jubba'i's doctrines in his fortieth year after asking him a question al-Jubba'i failed to resolve over the issue of the supposed divine obligation to abandon the good for the sake of the better (al-sâlih wa al-aslah). At that time he adopted the doctrines of the sifatiyya, those of Ahlu-s-Sunnah. He left Basra and came to Baghdad, taking fiqh from the Shafi`i jurist Abu Ishaq al-Marwazi (d. 340). He devoted the next twenty-four years to the refutation of "the Mu`tazila, the Rafida, the Jahmiyya, the Khawarij, and the rest of the various kinds of innovators" in the words of al-Khatib. His student Bundar related that his yearly expenditure was a meagre seventeen dirhams. His three best-known disciples were al-Bāhilī, aṣ-Ṣuʿlūkī, and Ibn Mujāhid, all of whom transmitted the doctrines of their master to what later became the flourishing school of Khorāsān. After al-Ashʿarī died, his disciples slowly disentangled the main lines of doctrine that eventually became the stamp of the Ashʿarite school.