The publication of expectations of a felicitous future examined in prior chapters did not go unnoticed by defenders of Lutheran doctrine. Some condemned these expectations of manifestations of the ancient heresy of chiliasm. This chapter provides a diachronic account of the evolution of the definitions of this heresy between ca. 1570 and 1630, drawing attention to the circulation of conflicting and contradictory definitions. Although these condemnations sought to define and defend confessional identity, they ultimately sowed confusion, and led to the retrospective condemnation of doctrines once considered orthodox.