Jacob Joseph Frank was a Polish-Jewish religious leader who claimed to be the reincarnation of the self-proclaimed messiah Sabbatai Zevi (1626–1676) and also of the biblical patriarch Jacob. The Jewish authorities in Poland excommunicated Frank and his followers due to his heretical doctrines that included deification of himself as a part of a trinity and other controversial concepts such as neo-Carpocratian "purification through transgression".

Sabbatai Zevi was an Ottoman Jewish mystic, and ordained rabbi from Smyrna. He was likely of Ashkenazi origin. Active throughout the Ottoman Empire, Zevi claimed to be the long-awaited Jewish Messiah and founded the Sabbatean movement.