The Holy Spirit, out of compassion for our weakness, comes to us even when we are impure. And if He finds our intellect truly praying to Him, He enters it and puts to flight the whole array of thoughts and ideas circling within it, and He arouses it to a longing for spiritual prayer.
Evagrius PonticusHe who has mastery over his incensive power has mastery also over the demons. But anyone who is a slave to it is a stranger to the ways of the Saviour, for as the Saviour enjoined us: 'Learn from Me; for I am gentle and humble in heart: and you will find rest for your souls' (Mt. 11:29). Now if a man abstains from food and drink, but becomes incensed to wrath because of evil thoughts, he is like a ship sailing the open sea with a demon for a pilot.
Evagrius PonticusIf your spirit still looks around at the time of prayer, then it does not yet pray as a monk. You are no better than a man of affairs engaged in a kind of landscape gardening.
Evagrius PonticusProvide yourself with such work for your hands as can be done, if possible, both during the day and at night, so that you are not a burden to anyone, and indeed can give to others, as St. Paul the Apostle advises (cf. I Thess. 2:9; Eph. 4:28). In this manner you will overcome the demon of listlessness and drive away all the desires suggested by the enemy; for the demon of listlessness takes advantage of idleness. 'Every idle man is full of desires' (Prov. 13:4 LXX).
Evagrius Ponticus