Evagrios the Solitary, also known as Evagrius of Pontus
Lived 346 – 399CE (questionable) as an early ascetic pioneer
Texts on Discrimination in Respect of Passions and Thoughts
Now what am I to say about the demon who makes the soul dull-minded? For I am afraid to write about him: how, at his approach, the soul departs from its own proper state and strips itself of reverence and the fear of God, no longer regarding sin as sin, or wickedness as wickedness; it looks on judgment and the eternal punishment of hell as mere words; it laughs at the fire which causes the earth to tremble; and, while supposedly confessing God, it has no understanding of His commandments. You may beat your breast as such a soul draws near to sin, but it takes no notice. You recite from the Scripture, yet it is wholly indifferent and will not hear. You point out its shame and disgrace among men, and it ignores you, like a pig that closes its eyes and charges through a fence. This demon gets into the soul by way of long-continuing thoughts of self-esteem; and unless ‘those days are shortened, no flesh will be saved’ (Matt. 24:22).
This is one of those demons that seldom approach brethren living in a community. The reason is clear: when people round us fall into misfortune, or are afflicted by illness, or are suffering in prison, or meet sudden death, this demon is driven out; for the soul has only to experience even a little compunction or compassion and the callousness caused by the demon is dissolved. We solitaries lack these things, because we live in the wilderness and sickness is rare among us. It was to banish this demon especially that the Lord enjoined us in the Gospels to call on the sick and visit those in prison. For ‘I was sick,’ He says, ‘and you visited Me'(Matt. 25:36).
But you should know this: if an anchorite falls in with this demon, yet does not admit unchaste thoughts or leave his cell out of lack of motivation, this means he has received the patience and self-restraint that come from heaven, and is blessed with good judgement. Those, on the other hand, who profess to practice godliness, yet choose to have dealings with people of the world, should be on their guard against this demon. I feel ashamed to say or write more about him.
Italics show my alterings
Translation from the Philokalia
found at: Holybooks.com