 Among the most important influences on Kant’s understanding of religion is no doubt his experience of Pietism, a reform movement within German Lutheranism which aimed to fulfill what it saw as the original intention of Martin Luther. According to the founders of Pietism, such as Philip Jacob Spener (1635–1705), this original intention required a more scrupulous religious and moral outlook, a deep personal devotion to increasing one’s own piety and that of others (through collegia pietatis, i.e., through private meetings among lay persons for development of personal holiness), and consequently exacting self-examination as well as the creation of a general culture of supporting progress in these matters. Pietists saw Orthodox Lutheranism, by contrast, as having become frozen in vain intellectualism, an adherence to over-subtle and lifeless formalisms, and ecclesiastical politics. As a consequence, Pietists sought a return what Spener referred to as “apostolic simplicity” in theological matters.