Jacob Joseph Frank was an 18th-century 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".