St. John Cassian (360-435) was influential to the establishment of medieval monasticism. He was trained by the hermits in Egypt, ordained deacon by the patriarch St. John Chrysostom in Constantinople, and founded the abbey of Saint-Victor at Marseille. He helped shape medieval monasticism through his works Institutes of the Monastic Life and The Conferences of the Desert Fathers. In The Conferences, Cassian provides the guidelines for how to translate the desert asceticism into urban environments and establishes the monastery as the training center for both new monks and new clerics, eliminating the division established between the two by St. Jerome.  Cassian’s Conferences were referenced by St. Benedict as he wrote his monastic rule over a century later.
 Stephen J. Joyce, “Contested Origins of Monasticism: Divergent Models of Authority,” Journal of the Australian Early Medieval Association 11 (2015), 11-16; “St. John Cassian, Monk,” Encyclopedia Britannica, last updated August 2020, https://www.britannica.com/biography/Saint-John-Cassian.