This study portrays a man and an age. Yom-Tov Lipmann Heller (1578-1654), author of the famous Mishnah commentary Tosafot yom tov, was a major talmudist, a disciple of the legendary Rabbi Judah Loew of Prague, and himself the distinguished chief rabbi of Prague and Cracow. The time in which he lived began as a 'golden age' for the Jews of Prague and the Jews of Poland, an age of prosperity and the rise of Jewish mysticism. During Heller's lifetime,...