 A later orthodox theologian, Valentin Ernst Löscher, took part in a controversy against Pietism.Mediaeval mystical tradition continued in the works of Martin Moller, Johann Arndt and Joachim Lütkemann.Pietism became a rival of orthodoxy but adopted some orthodox devotional literature, such as those of Arndt, Christian Scriver and Stephan Prätorius, which have often been later mixed with Pietistic literature.