E. Kessler has argued that the Dionysian cult developed into strict monotheism by the 4th century AD; together with Mithraism and other sects, the cult formed an instance of "pagan monotheism" in direct competition with Early Christianity during Late Antiquity.[237] Scholars from the 16th century onwards, especially Gerard Vossius, also discussed the parallels between the biographies of Dionysus/Bacchus and Moses (Vossius named his sons Dionysius and Isaac). Such comparisons surface in details of paintings by Poussin.[238]