By St. John Cassian
(Conferences, 2.5)
And so by the judgment of the blessed Anthony as well as of all others it has been laid down that it is discernment which leads a fearless monk by fixed stages to God, and preserves the virtues mentioned above continually intact, by means of which one may ascend with less weariness to the extreme summit of perfection, and without which even those who toil most willingly cannot reach the heights of perfection. For discernment is the mother of all virtues, as well as their guardian and regulator.
And to support this judgment delivered of old by the blessed Anthony and the other fathers by a modern instance, as we promised to do, remember what you lately saw happen before your very eyes, I mean, how the old man Heron, only a very few days ago was cast down by an illusion of the devil from the heights to the depths, a man whom we remember to have lived for fifty years in this desert and to have preserved a strict continence with special severity, and who aimed at the secrecy of solitude with marvelous fervor beyond all those who dwell here. By what device then or by what method was he deluded by the deceiver after so many labors, and falling by a most grievous downfall struck with profound grief all those who live in this desert? Was it not because, having too little of the virtue of discernment he preferred to be guided by his own judgment rather than to obey the counsels and conference of the brethren and the regulations of the elders?
