theologian of Constantinople (now Istanbul), the only scholar to seek a philosophical basis for Karaite beliefs. Karaism, a Jewish movement originating in 8th-century Iran, rejected the oral tradition and challenged the authority of the Talmud (Talmud and Midrash), the rabbinical compendium of law, lore, and commentary.

Aaron ben Elijah's views are summarized in his compilation of Karaite lore, in three books. In the first book, ʿEtz ḥayyim (1346; “Tree of Life”), modeled after the 12th-century Jewish philosopher Maimonides' (Maimonides, Moses) Moreh nevukhim (The Guide for the Perplexed), he attempts to create a Karaite counterpart to Maimonides' Aristotelian outlook. In the second book, Gan Eden (1354; “The Garden of Eden”), he attempts to justify the Karaite code of law. The third book, Keter Torah (1362; “Crown of Law”), is a commentary on the Pentateuch, based on literal interpretations of the text.