In the second place we should be careful to see that no wrong interpretation fixed on to the pure gold of Scripture deceives us as to the value of the metal: by which means the devil in his craft tried to impose upon our Lord and Saviour as if He was a mere man, when by his malevolent interpretation he perverted what ought to be understood generally of all good men, and tried to fasten it specially on to Him, who had no need of the care of the angels: saying, “For He shall give His angels charge concerning Thee, to keep Thee in all Thy ways: and in their hands they shall bear Thee up, lest at any time Thou dash Thy foot against a stone,” (Matt. iv. 6; Ps. xc. 11, 12) by a skilful assumption on his part giving a turn to the precious sayings of Scripture and twisting them into a dangerous sense, the very opposite of their true meaning, so as to offer to us the image and face of an usurper under cover of the gold colour which may deceive us.
Or whether he tries to cheat us with counterfeits, for instance by urging that some work of piety should be taken up which as it does come from the true minds of the fathers, leads under the form of virtue to vice; and, deceiving us either by immoderate or impossible fasts, or by too long vigils, or inordinate prayers, or unsuitable reading, brings us to a bad end. Or, when he persuades us to give ourselves up to mixing in the affairs of others,….
Or else when he incites a man to desire the holy office of the clergy under the pretext of edifying many people, and the love of spiritual gain, by which to draw us away from the humility and strictness of our life….
All of which things, although they are opposed to our salvation and to our profession, yet when covered with a sort of veil of compassion and religion, easily deceive those who are lacking in skill and care. For they imitate the coins of the true king, because they seem at first full of piety, but are not stamped by those who have the right to coin, i.e., the approved Catholic fathers, nor do they proceed from the head public office for receiving them, but are made by stealth and by the fraud of the devil, and palmed off upon the unskilful and ignorant not without serious harm.
Cassian’s Conferences, 1st Conference of Abbot Moses, chapter 20, NPNF, 2nd series, Vol.11