John Slotanus
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(SCHLOTTANUS, VAN DER SLOOTIEN), (JOHN GEFFEN)
Polemical writer; born at Geffen, Brabant; died at Cologne, 9 July, 1560. He joined the Dominican order at Cologne about 1525. For many years he ably defended the Faith against the heretics by preaching and writing. Later he taught sacred letters at Cologne, and in 1554 was made a doctor of theology. About this same time he became prior of his convent at Cologne, and as such exercised the offices of censor of the faith and papal inquisitor throughout the Archdiocese of Cologne and the Rhine country. In the discharge of these responsible duties Slotanus came into conflict with the learned Justus Velsius, who in 1556, on account of heretical teachings, was obliged to leave Cologne. The vehement writings which Velsius afterwards published against the Cologne theologians moved Slotanus to write two works in which nearly all the heretical doctrines of his time are discussed with admirable skill.
Among his various works those most worthy of mention are: "Disputationum adversus hæreticos liber unus" (Cologne, 1558); "De retinenda fide orthodoxa et catholica adversus hæreses et sectas" (Cologne, 1560); "De barbaris nationibus convertendis ad Christum" (Cologne, 1559). In the last-named work Slotanus witnesses to the ardent missionary zeal which fired the religious men of his time.
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