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Isaac ben Solomon


ISAAC BEN SOLOMON (1755–1826), prominent *Karaite scholar and spiritual leader from Chufut-Qaleh, a reformer of the Karaite calendar system, and authority on religious law. He was a disciple of Isaac ben Joseph *Kalfa. At the age of 17 he worked for Benjamin *Aga and went with him to St. Petersburg. After returning to Chufut-Qaleh he engaged in commerce but went bankrupt. In 1776 he was appointed by Benjamin Aga to teach at the school in Chufut-Qaleh and soon was appointed as a hakham of the community at the age of 21. In 1795 he traveled with Benjamin Aga and some other community leaders to St. Petersburg with a special mission to the government, which achieved exemption for Crimean Karaites from the double taxation imposed on all the Jews of the Russian Empire, and the attainment of other rights. Isaac was a physician, who cured Jews and non-Jews of Chufut-Qaleh and the surrounding area. He had a wide knowledge of astronomy, which he studied for six months during his stay in St. Petersburg. In 1806 he was one of the founders of a publishing house in Chufut-Qaleh. He read proofs of Karaite books and prayer books that were printed there and sometimes added introductions to them. Isaac was a prominent religious authority in his generation, establishing several new regulations of Karaite halakhah: He forbade the ritual purification of golden and silver vessels without passing them through fire; forbade moving things in the public domain on Shabbat; permitted weddings during the Ten Days of Penitence and so on. His most important innovation was calendar reform (1779). It was an attempt to establish a uniform permanent system of calendation among the Karaites, which was not based on observation. It was supported by most scholars in Crimea and some other communities. His initiative led to a fierce dispute among the communities of Constantinople and the Crimea that lasted 18 years. The opposition to this reform was headed by *Benjamin ben Elijah Duwan, a Karaite leader from Evpatoria. In 1781 Benjamin Duwan came to Chufut-Qaleh at the head of a group of Karaite worthies of his town in order to conduct a debate with Isaac ben Solomon. According to Isaac's report, Benjamin was defeated, and Isaac's calendar calculation was supported by the majority. His book Or ha-Levana (Zhitomir 1872) is a detailed exposition of his calendar reform. Isaac also wrote the following works: Iggeret Pinnat Yiqrat (Evpatoria 1834), a theological treatise based on the ten principles of faith formulated by Elijah *Bashyazi in Adderet Eliyahu (with a Tatar translation of the principles; Nemoy published an English abridged translation of the work, with a detailed appraisal [see bibl.]); it includes many refutations ("replies") of philosophical positions, in which he actually criticized Bashyazi for his theological innovations; Moladot – lunar calculations for 34 years for the years 1806–40 (Chufut-Qaleh, 1806) and a commentary on the Song of Songs (Ms b 316 at the St. Petersburg Institute of Oriental Studies of the Russian Academy). He also wrote many liturgical poems, which were included in the Karaite Siddur. Many letters, responsa, and short treatises by him are preserved in manuscripts the St. Petersburg Institute of Oriental Studies of the Russian Academy and the Russian National Library.


G. Akhiezer, in: M. Polliack (ed.), Karaite Judaism (2003), 740–2, and index; E. Deinard, Massa Krim (1878), 70; R. Fahn, Sefer ha-Kara'im (1929), 79–81; J. Mann, Texts, 2, (1935), index; L. Nemoy, in: jqr, 80:1–2 (1989), 49–85.

[Golda Akhiezer (2nd ed.)]

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