Known most widely for his role in the civil rights and peace movements of the 1960s, Abraham Joshua Heschel made major scholarly contributions to the fields of biblical studies, rabbinics, medieval Jewish philosophy, Hasidism, and mysticism. Yet, his most ambitious scholarly achievement, his three-volume study of Rabbinic Judaism, is only now appearing in English. Heschel's great insight is that the world of rabbinic thought can be divided into two types or schools, those of Rabbi Akiva and Rabbi Ishmael, and that the historic disputes between the two are based on fundamental differences over the nature of revelation and religion. Furthermore, this disagreement constitutes a basic and necessary ongoing polarity within Judaism between immanence and transcendence, mysticism and rationalism, neo-Platonism and Aristotelianism. Heschel then goes on to show how these two fundamental theologies of revelation may be used to interpret a great number of topics central to Judaism.