Observe your thoughts, and beware of what you have in your heart and your spirit, knowing that the demons put ideas into you so as to corrupt your soul by making it think of that which is not right, in order to turn your spirit from the consideration of your sins and of God.
He who wishes to tear up the account of his sins and to be inscribed in the Divine book of the saved, can find for this purpose no better means than obedience.
Do not neglect the practice of the virtues; if you do, your spiritual knowledge will decrease, and when famine occurs you will go down into Egypt (Genesis 41:57, 46:6).
And Jesus, when He was baptised, went up straightway out of the water; and lo, the heavens were opened unto Him, and He saw the Spirit of God descending like a dove, and lighting upon Him; and lo, a voice from heaven saying: 'This is My beloved Son, in whom I am well pleased.' The Spirit did not descend on Christ while He was down in the water, but when He came out of it. By this, the wisdom of God seeks to show us that the Spirit of God does not descend on the old man, who is alive to sin and dead to God, but only on the man spiritually re-born, who has died to sin and come alive to God.
If your heart has been softened either by repentance before God or by learning the boundless love of God towards you, do not be proud with those whose hearts are still hard. Remember how long your heart was hard and incorrigible. Seven brothers were ill in one hospital. One recovered from his illness and got up and rushed to serve his other brothers with brotherly love, to speed their recovery. Be like this brother. Consider all men to be your brothers, and sick brothers at that. And if you come to feel that God has given you better health than others, know that it is given through mercy, so in health you may serve your frailer brothers.
Even a pious person is not immune to spiritual sickness if he does not have a wise guide -- either a living person or a spiritual writer. This sickness is called prelest, or spiritual delusion, imagining oneself to be near to God and to the realm of the divine and supernatural. Even zealous ascetics in monasteries are sometimes subject to this delusion, but of course, laymen who are zealous in external struggles (podvigi) undergo it much more frequently. Surpassing their acquaintances in struggles of prayer and fasting, they imagine that they are seers of divine visions, or at least of dreams inspired by grace. In every event of their lives, they see special intentional directions from God or their guardian angel. And then they start imagining that they are God's elect, and often try to foretell the future. The Holy Fathers armed themselves against nothing so fiercely as against this sickness -- prelest.
