On the Duties of Monks

St. Theodore the Studite ca. 759-826

If there are any monks in our day, they will be proved by their works. The work of a monk is to not tolerate any innovations whatsoever as pertains to the Gospel, that they not become examples to laymen as proposing heresy and communion with heretics, for they will give account for their [the laity’s] loss [of salvation]. (Letter 79, to Abbot Theophilos, PG 99, 1049)