The heart which is constantly guarded, and is not allowed to receive the forms, images and fantasies of the dark and evil spirits, is conditioned by nature to give birth from within itself to thoughts filled with light. For just as coal engenders a flame, or a flame lights a candle, so will God, who from our baptism dwells in our heart, kindle our mind to contemplation when He finds it free from the winds of evil and protected by the guarding of the intellect.
Mind is not soul, but a gift from God which saves the soul. A mind pleasing to God flows ahead of the soul and counsels it to scorn the temporal, material and corruptible, and to love blessings that are eternal, incorruptible and immaterial, so that, while living in the body, man should, with his mind, apprehend and contemplate the heavenly and the divine. In this way a God-loving mind is a benefactor and savior of the human soul.
The hour of death will come upon us, it will come, and we shall not escape it. May the prince of this world and of the air (cf. John 14:30; Eph. 2:2) find our misdeeds few and petty when he comes, so that he will not have good grounds for convicting us. Otherwise we shall weep in vain. 'For that servant who knew his lord's will and did not do it as a servant, shall be beaten with many stripes' (cf. Luke 12:47).
Have you realized that the world and worldly cares do not hinder in fulfilling God's commandments, when there is zeal and attention? That silence and retirement from the world are useless, if laziness and negligence prevail?
God seeks nothing else from us men except that we do not sin; this alone. But this is not a work of law; it is rather a careful guarding of the image and dignity from above. In these things, affirmed in our nature and bearing the radiant garment of the Spirit, we shall abide in God and He in us. We shall be called good, and sons of God by adoption, marked in the light of our knowledge of God.
My children, desire to purify your hearts from envy and from anger with each other, lest death should overcome you, and you will be counted among the murderers. For whosoever hates his brother, kills a soul.
It is important also to study our God-given faith in detail, since he who is indifferent toward truth is in danger of becoming easy prey for false teachers.
The roof of any house stands upon the foundations and the rest of the structure. The foundations themselves are laid in order to carry the roof. This is both useful and necessary, for the roof cannot stand without the foundations and the foundations are absolutely useless without the roof-- no help to any living creature. In the same way the grace of God is preserved by the practice of the commandments, and the observance of these commandments is laid down like foundations through the gift of God. The grace of the Spirit cannot remain with us without the practice of the commandments, but the practice of the commandments is of no help or advantage to us without the grace of God.
Watchfulness and the Jesus Prayer, as I have said, mutually reinforce each other, for close attentiveness goes with constant prayer, while prayer goes with close watchfulness and attentiveness of intellect.
As earth thrown over it extinguishes a fire burning in a stove, so worldly cares and every kind of attachment to something, however small and insignificant, destroy the warmth of the heart which was there at first.
No man, wise in his own opinion, because he has studied all the sciences and is learned in external wisdom, will ever penetrate God's mysteries or see them unless he first humbles himself and becomes foolish in his heart, repudiating his self-opinion together with his acquirements of learning. For a man who acts thus and follows with undaunted faith those who are wise in things Divine, is guided by them and with them enters into the city of the living God, and, taught and enlightened by the Holy Spirit, sees and knows things which no one else can see or know. Thus he becomes taught of God.
Labor to acquire meekness. Concerning the heavenly virtues, meekness and humility, the Lord Himself teaches us, saying: Learn of Me, for I am meek and humble in heart; and ye shall find rest unto your souls (Matt. 11:29). Learn not from angels, nor from men, but from Me, He says; that is, from the higher wisdom.
The road into the Kingdom of Heaven was made by the Lord Jesus Christ, and He was the first one who traveled it. The Bible teaches that only he who follows Jesus can reach His Kingdom. But how can one follow Him? Hear what our Savior says about this: Whoever desires to come after Me, let him deny himself, and take up his cross, and follow Me (Mark 8:34). The words whoever desires mean that Christ does not compel anyone to follow Him. He has no need of the unwilling ones, but He desires that each person freely follow Him. Consequently, only those who willingly choose the Savior's path reach the Kingdom of Heaven.
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.