Hasidic Jews affirm devotion to a Rebbe, a charismatic spiritual master (tzaddik) who guides his community, and the pursuit of God through joy, fervour, and inwardness. Arising in eighteenth-century Eastern Europe with the Baal Shem Tov, Hasidism taught that the unlettered could serve God through sincerity, song, and heartfelt prayer as truly as the scholar through study, and that the divine presence fills all things, so that even ordinary acts can be raised to holiness. The Rebbe is regarded as a channel of blessing and counsel, binding the community around his court and dynasty.
Early Hasidism faced fierce opposition from the Mitnagdim ("opponents"), led by the eminent Vilna talmudist Elijah ben Solomon Zalman, the Vilna Gaon, who saw in Hasidic ecstatic prayer, elevation of the Rebbe's authority, and relative de-emphasis of rigorous talmudic study a dangerous departure from normative rabbinic Judaism, reminiscent of the antinomian dangers exposed by the earlier false-messiah movement of Shabbetai Tzvi. The Vilna community issued writs of excommunication (cherem) against Hasidim beginning in 1772 and renewed them in subsequent years, and the conflict remained bitter for decades before the two camps largely reconciled, within Ashkenazi Orthodoxy, in the face of the shared external challenges posed by Reform Judaism and secularisation in the nineteenth century.