born 1579, Wallerstein, Bavaria died Sept. 7, 1654, Kraków, Pol. Bohemian Jewish religious scholar. After serving as rabbi in Moravia and Vienna, he became chief rabbi in Prague in 1627. He was forced to collect a heavy tax imposed on Jews by Ferdinand II during the Thirty Years' War, damaging his reputation in the Jewish community. Later, as rabbi in Volhynia, he earned the enmity of wealthy Jews for denouncing simony. From 1643 he was chief rabbi in Kraków. He is best known for his commentary on the Mishna, The Additions of Yom Tov (1614-17)