Dāwūd al-Muqammiṣ

Dāwūd ibn Marwān al-Muqammiṣ (or al-Muqammaṣ) lived in Syria and Iraq and is the first medieval Jewish philosopher whose writings survive. Al-Muqammiṣ allegedly converted to Christianity before returning to Judaism; his familiarity with Christian dogma is evident in his anti-Christian polemics. He was a kalām (rationalist theology) thinker, and his Twenty Chapters (ʻIshrūn maqālāt) stresses the ideas of divine unity and justice, two of the main issues dealt with in kalām treatises. Al-Muqammiṣ also composed a partially surviving commentary on Genesis. Although it has not been determined if he was a Rabbanite or a Karaite, he influenced Se‘adya Ga’on, and many later Judeo-Arabic authors refer to him.