TWERSKY, ISADORE (1930–1997), scholar and teacher. Born in Boston, Massachusetts, the son of R. Meshullam Zalman Twersky (Tolnaer Rebbe), a member of the well-known ḥasidic dynasty, Twersky was ordained as a rabbi by the Isaac Elchanan Yeshiva (University). At Harvard University he earned a bachelor's degree in 1952, a master's in 1953, and a doctorate in 1956. He became a faculty member at Harvard in 1956 as professor of Hebrew literature and philosophy, and chairman of the Department of Near Eastern Languages from 1965. He served as director of Harvard's Center for Jewish Studies from 1978 to 1993.
Twersky's formidable expertise in Jewish literature encompassed such areas as the rabbinic texts, Bible commentaries, and legal writing of the Middle Ages. He was a fellow of the American Academy for Jewish Research and the American Academy of Arts and Sciences. In 1989 he won a Guggenheim Fellowship.
His published works include Rabad of Posquières, a 12th-Century Talmudist (1962); Judaism and World History (1969); and A Maimonides Reader (1969). He edited Studies in Medieval Jewish History and Literature (vol. 1, 1979; vol. 2, 1985; vol. 3, 2000); Danzig: Between East and West (1985); Jewish Thought in the 17th Century (1987); and Studies in Maimonides (1991).
Twersky was the son-in-law of the eminent rabbinic thinker and scholar Rabbi Joseph *Soloveitchik.