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Klein, Isaac


KLEIN, ISAAC (1905–1979), Conservative rabbi, leader, and posek (halakhic authority). Klein was born and raised in the town of Palanka in Ruthenia, Hungary. In 1921, he and his family immigrated to New York to join his father, who had moved there before World War i. Klein received a B.A. from City College in 1931. He began to study at *Yeshiva University, but transferred to the *Jewish Theological Seminary (jts) where he was ordained in 1934. After ordination, he continued to study Talmud and Codes. In 1948, Klein received a Ph.D. from Harvard University.

During the 45 years of his rabbinate, Rabbi Klein served as a pulpit rabbi, army chaplain, and visiting professor at two rabbinical schools. His pulpits were in Springfield, Mass. (1934–53) and Buffalo, n.y. (1953–72). Klein also served as a U.S. Army chaplain during World War ii (1942–46) and as President *Truman's adviser on Jewish Religious Affairs to the U.S. High Commissioner of Germany (1949–50), helping to resettle displaced persons and reorganize Jewish communities in Germany after the Shoah.

Beginning in 1959, Klein served as visiting associate professor of Jewish Law at jts, where he taught Practical Halakhah (Jewish Law). When he retired from the pulpit in 1972, he wintered in Los Angeles where he taught Jewish Law at the University of Judaism.

Klein was also a leader of the Conservative Movement, serving as president of the *Rabbinical Assembly (1958–60). He was an active member of the Committee on Jewish Law and Standards (1935–79) and served on the Joint Bet Din of the Conservative Movement.

Klein published a total of nine books, which can conveniently be divided into three categories: translations of three of the fourteen volumes of the Yale Judaica Series; three books relating his experiences as an army chaplain and pulpit rabbi; and three halakhic works. The third of these is his magnum opus, A Guide to Jewish Religious Practice (1979), which is based on the course he taught for many years at jts. It combines a survey of most aspects of practical halakhah together with introductions explaining ta'amei ha-mitzvot, the reasons for the commandments, based on a wide range of rabbinic, medieval, and modern sources.

At the end of his 1968 article on "The Shulḥan Arukh after 400 Years," Rabbi Klein explains that there is a need to update the Shulhan Arukh "at least for the Conservative Movement, and hopes that it will be helpful to kelal Yisrael (the collective Jewish People)." He goes on to say that the person who writessuch a code must possess scholarship, saintliness, humility, and a deep awareness of and sympathy for the needs of the Jewish community. Rabbi Klein was such a person and that is why his Guide has become a veritable Kizzur Shulhan Arukh for Conservative Jews.


H. Dicker, Piety and Perseverance: Jews from the Carpathian Mountains (1981), 33, 122–24; M. Lockshin, Tradition, 18:2 (Summer 1980), 227–30; P. Nadell, Conservative Judaism: A Biographical Dictionary and Sourcebook (1988), 159–61.

[David Golinkin (2nd ed.)]

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