John Cassian (c. AD 360 – c. 435) was a Christian monk and theologian celebrated in both the Western and Eastern churches for his mystical writings. Cassian is noted for his role in bringing the ideas and practices of Christian monasticism to the early medieval West.
Cassian was born around 360, most likely in the region of Scythia Minor. The son of wealthy parents, he received a good education: his writings show the influence of Cicero and Persius. He was bilingual in Latin and Greek.
As a young adult he traveled to Palestine with an older friend Germanus, with whom he would spend much of the next twenty-five years. There they entered a hermitage near Bethlehem. After remaining in that community for about three years, they journeyed to the desert of Scete in Egypt, which was rent by Christian struggles. There they visited a number of monastic foundations.
Approximately fifteen years later, Cassian and Germanus faced the Anthropomorphic controversy provoked in letter form by Theophilus, Archbishop of Alexandria. Cassian noted that the majority of the monks received the message of their patriarch "with bitterness", and charged Theophilus with heresy for impugning the plain teaching of scripture.
Cassian was ordained a deacon and became a member of the clergy attached to the patriarch while the struggles with the imperial family ensued. When the patriarch was forced into exile from Constantinople in 404, the Latin-speaking Cassian was sent to Rome to plead his cause before Pope Innocent I.
Cassian's achievements and writings influenced Benedict of Nursia, who incorporated many of the principles into his monastic rule, and recommended to his own monks that they read the works of Cassian. Since Benedict's rule is still followed by Benedictine, Cistercian, and Trappist monks, John Cassian's thought still exercises influence over the spiritual lives of thousands of men and women in the Latin Church.
Cassian died in 435 at Marseille.
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