Karaites Real and Imagined: Three Cases of Jewish Heresy

There is a widespread misperception that Judaism is a religion of praxis rather than belief, in which adhering to behavioural precepts, rather than particular doctrines, renders one a member in good standing.1 But was premodern Judaism nothing but a congeries of rabbinic dictates on how to observe the commandments properly? Was belief really so marginal a consideration in determining the boundaries of the Jewish oecumene? What has prevented much of modern Jewish historiography from focusing on struggles over doctrine? The first modern works on Spinoza are a case in point, insisting that he was excommunicated from the Amsterdam Sephardi community in 1656 for his acts rather than his opinions. But the preface to the writ excommunicating him cites both ‘the abominable heresies which he practiced and taught and … his monstrous deeds’, a phrase that should probably be read as a hendiadys referring to Spinoza's teaching of doctrine alone.2 The history of the Jews is filled with excommunications for heresy of which Spinoza's was not the first. From late Antiquity on, both rabbinic and lay authorities imposed the ban on men and women whom they accused not only of behavioural infractions but of doctrinal error as well.3