Saint John Cassian. "Conferences".
First Conference of Abbot Moses. On the Goal or Aim of the Monk.
Chapter XXI. Of the illusion of Abbot John.
In this manner we have heard that Abbot John who lived at Lycon, was recently deceived. For when his body was exhausted and failing as he had put off taking food during a fast of two days, on the third day while he was on his way to take some refreshment the devil came in the shape of a filthy Ethiopian, and falling at his feet, cried "Pardon me because I appointed this labour for you." And so that great man, who was so perfect in the matter of discretion, understood that under pretence of an abstinence practised unsuitably, he was deceived by the craft of the devil, and engaged in a fast of such a character as to affect his worn out body with a weariness that was unnecessary, indeed that was harmful to the spirit; as he was deceived by a counterfeit coin, and, while he paid respect to the image of the true king upon it, was not sufficiently alive to the question whether it was rightly cut and stamped. But the last duty of this "good money-changer," which, as we mentioned before, concerns the examination of the weight, will be fulfilled, if whenever our thoughts suggest that anything is to be done, we scrupulously think it over, and, laying it in the scales of our breast, weigh it with the most exact balance, whether it be full of good for all, or heavy with the fear of God: or entire and sound in meaning; or whether it be light with human display or some conceit of novelty, or whether the pride of foolish vain glory has not diminished or lessened the weight of its merit. And so straightway weighing them in the public balance, i.e., testing them by the acts and proofs of the Apostles and Prophets let us hold them as it were entire and perfect and of full weight, or else with all care and diligence reject them as imperfect and counterfeit, and of insufficient weight.