AARON OF JERUSALEM (called also Abu al-Faraj Harun ben Alfarez, the Grammarian of Jerusalem):
Karaite of the eleventh century. He was acknowledged by the Rabbinites as one of the principal representatives of Karaitic learning and as a great authority on grammar and exegesis. He is quoted by Abraham ibn Ezra in the preface to his "Moznayim" as "the sage of Jerusalem, not known to me by name, who wrote eight books on grammar, as precious as sapphire." Moses ibn Ezra refers to him as "the sage of Jerusalem who wrote the 'Mushtamil,'" and also quotes him as "Sheik Abu al-Faraj of Jerusalem, who is no adherent of our religious community." Judah ibn Balaam likewise mentions "the grammarian of the Holy City"; and Abu al-Walid in his "Riḳmah" relates that Jacob de Leon brought him from Jerusalem "the copy of a book by an author who lived there, but whose name he refrains from mentioning," because, as Bacher surmises, he was a Karaite. Little was known of Aaron until Neubauer discovered, among the manuscript collection of Firkovitch in St. Petersburg, important fragments in Arabic of the "Mushtamil" (The Comprehensive), a Hebrew grammar consisting of eight books. Bacher, while studying these fragments, succeeded in rediscovering the unknown grammarian. S. Poznanski published some valuable specimens of Aaron's work; and, following a suggestion of Harkavy, he threw new light on the author and some other works of his—namely, the "Kitab al-Kafi," a commentary on the Pentateuch, often quoted by Karaite writers, and a lexicographical work bearing the title "Sharḥ Alalfaẓ," a part of which is extant in the British Museum.
- Fürst, Gesch. d. Karäert. i. 99, 100;
- Bacher, in Rev. Ét. Juives, xxx. 232-256;
- Poznanski, ibid., 1896, xxxiii. 24-39, 197-218;
- Pinsker, Liḳḳuṭe Ḳadmoniot, pp. 109 et seq.