David Abu Sulayman ibn Marwan al-Muqqamaá¹£ al-Raqqi ( translit.: Dawud ibn Marwan al-Muqammis; died c. 937) was a philosopher and controversialist, the author of an early Jewish philosophical work of the Middle Ages. He was a native of Raqqa, Mesopotamia, hence his laqab. Abraham Harkavy derives his nisba from the Arabic root qammaá¹£ "to leap," interpreting it as referring to his asserted change of faith. The name is written al-qumisi in Masudi's Al-Tanbih (ed. De Goeje, p. 113), in a Karaite Jewish commentary to Leviticus and a manuscript copy of Yefet ben Ali's commentary to the same book, and is perhaps a derivative from the city of Qumis, Iran. Another Karaite bears the name Daniel al-Kumisi, and in al-Hiti's chronicle, this name is also spelled with a tsade (Jew. Quart. Rev. ix.432).
David, the father of Jewish philosophy, was almost unknown until the late 19th century. The publication of Judah ben Barzillai's commentary to the Sefer Yetzirah (Mekitze Nirdamim, 1885), in which is found a poor Hebrew translation of the ninth and tenth chapters of David's philosophical work, first brought the latter into notice. Barzilai says that he does not know whether David was one of the geonim but claims to have heard that Saadia Gaon had known him and had profited from his lessons.
Jacob Qirqisani reports that he converted to Christianity, and then back to Judaism.
In 1898, Harkavy discovered in the National Library of Russia fifteen of the twenty chapters of David's philosophical work entitled ÿIshrà «n maqÃÂlÃÂt "Twenty Treatises". The subject matter is as follows:
David, like other Karaites such as Joseph ben Abraham and Qiriqisani, were Mu'tazilites, which was especially visible in his chapter on the attributes of God, wherein he holds that, though we speak of these attributes as we speak of human attributes, the two can not be compared, since nothing comes to Him through the senses as is the case with man. God's "life" is a part of His "being," and the assumption of attributes in the Deity cannot affect His unity. "Quality" can not be posited of the Deity. In his tenth chapter, "Rewards and Punishments," David holds that these are eternal in the world to come. This chapter has many points in common with Saadia Gaon, drawing from the same source.
David quotes two others of his works which are no longer in existence: KitÃÂb fë l-Budà «d and KitÃÂb fë ArḠal-MaqÃÂlÃÂt ÿalàl-Maná¹Âiq, on the categories. In one passage, David relates that he had a philosophical disputation in Damascus with a Muslim scholar, Shabib al-Baá¹£ri. A fragment of another work, Kitab al-Tawḥëd "Book on the Unity (of God)," has been discovered among genizah fragments and has been published by Elkan Nathan Adler and Isaac Broydé in Jew. Quart Rev. (xiii.52 et seq.). David does not betray his Jewish origin in his philosophical work. Contrary to the practice of Saadia, Bahya ibn Paquda, and other Jewish philosophers, he never quotes the Bible, but cites Greek and Arab philosophers. It is possible that this accounts for the neglect of his work by the Jews.