KALFA, ISAAK BEN JOSEPH (d. 1801), Karaite scholar, hazzan, and teacher of Torah from *Chufut-Qaleh. He was a head of a study house where he taught both Karaite and Rabbanite treatises. One of his disciples was *Isaac ben Solomon, who became one of the last prominent scholars of the Crimea and who established the calendar reform (1779), which was supported by most scholars in Crimea and some other Karaite communities. Kalfa wrote a book on ritual slaughter and about the 10 principles of the Karaite faith, Ziz Nezer ha-Kodesh and a number of liturgical poems, some of which were included in Karaite siddurim. He corresponded with the Karaite community in Jerusalem and sent donations there.
G. Akhiezer, in: M. Polliack (ed.), Karaite Judaism (2003), 742; Mann, Texts, 2 (1935), index, 1552.