When praying, endeavor by every means to feel in your heart the truth and the power of the words of the prayer; feed yourself upon them as upon an imperishable food; water your heart with them as with a dew; and warm yourself by them as by means of a beneficial fire.
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.
As a ray of sun, passing through a crack, lights everything in the house and shows up even the finest dust, so the fear of the Lord, entering a man's heart, reveals to him all his sins.
Reverence with all the powers of your soul all the sacraments, and say to yourself in respect to every sacrament before the celebration or the communion of it: `This is God's mystery. I myself am only the unworthy witness or partaker of it.' Otherwise our proud intellect even wishes to search out God's mystery, and, if unable to penetrate it, rejects it as not coming under the small measure of our intellect.
You must flee from sensual things. Verily, every time a man comes close to a struggle with sensuality, he is like a man standing at the edge of a deep lake, and the enemy throws him in whenever he likes. But if the man lives far from sensual things, he is like one who stands at a distance from the lake, so that even if the enemy entices him in order to throw him to the bottom, God sends him help at the very moment that the enemy is drawing him away and doing him violence.
Just as over-drinking is a matter of habit, so too from habit comes over-sleeping. Therefore we must struggle with the question of sleep, especially in the early days of obedience, because a long-standing habit is difficult to cure.
There is nothing impossible unto those who believe; lively and unshaken faith can accomplish great miracles in the twinkling of an eye. Besides, even without our sincere and firm faith, miracles are accomplished, such as the miracles of the sacraments; for God's Mystery is always accomplished, even though we were incredulous or unbelieving at the time of its celebration. 'Shall their unbelief make the faith of God without effect?' (Rom. 3:3). Our wickedness shall not overpower the unspeakable goodness and mercy of God; our dullness shall not overpower God's wisdom, nor our infirmity God's omnipotence.
God, the Word, made man for the salvation of our race, aware of the exceeding frailty and misery of our nature, hath not even here suffered our sickness to be without remedy. But like a skillful doctor, he hath mixed for our unsteady and sin loving heart the potion of repentance, prescribing this for the remission of sins. For after we have received the knowledge of the truth, and have been sanctified by water and the Spirit, and cleansed without effort from all sin and all defilement, if we should happen to fall into any transgression, there is, it is true, no second regeneration made within us by the Spirit through baptism in the water of the font, and wholly recreating us (that gift is given once for all); but, by means of painful repentance, hot tears, toils and sweats, there is a purifying and pardoning of our offences through the tender mercy of our God. For the fount of tears is also called baptism, according to the grace of the Master.
What does the daily invocation of the saints signify - of different ones each day, during the whole year, and during our whole life? It signifies that God's saints, as our brethren - but perfect - live, and are near us, ever ready to help us, by the grace of God. We live together with them in the house of our Heavenly Father, only in different parts of it. We live in the earthly, they in the heavenly half, but we can converse with them, and they with us. God's saints are near to the believing heart, and are ready in a moment to help those who call upon them with faith and love
He who refuses to accept a criticism, just or not, renounces his own salvation, while he who accepts it, hard or not though it may be, will soon have his sins forgiven.
During the divine services, and at the very moment when the Mysteries (e.g., Holy Communion) are being accomplished, this vile enemy often blasphemes the Lord and the holy Sacrifice that is being consecrated. Wherefore, we clearly learn that it is not our soul that pronounces these unspeakable, godless and unthinkable words within us, but the God-hating fiend who fled from Heaven for uttering blasphemies against the Lord there too, as it would seem. For if these shameless and disgraceful words are my own, how could I worship after receiving the Gift? How can I praise and revile at one and the same time?
If some Christians cannot comprehend our Orthodox faith, its Sacraments, it proves that the minds and hearts of such persons are too impure and passionate to bear its purity and brightness, just as sick eyes cannot bear the light of the sun. This heavenly treasure can only be comprehended by the hearts of those who free their minds and feelings from worldly attachments.
In detachment, the spirit finds quiet and repose for coveting nothing. Nothing wearies it by elation, and nothing oppresses it by dejection, because it stands in the center of its own humility.
We firmly believe that the Church will never fall, will never waiver and will not be destroyed. For this is what Christ taught, by Whom the heavens were established and the earth was founded, and stands firmly as the Holy Spirit says” (Ps. 32:6). The Antichrist will lure to himself 'those who have a weak and feeble mind, will seduce and will tear them away from the living God.'
The enemy of our salvation especially strives to draw our heart and mind away from God when we are about to serve Him, and endeavours to adulterously attach our heart to something irrelevant. Be always, every moment, with God, especially when you pray to Him. If you are inconstant, you will fall away from life, and will cast yourself into sorrow and straitness.
Oh, what great happiness and bliss, what exaltation it is to address oneself to the Eternal Father. Always, without fail, value this joy which has been accorded to you by God's infinite grace and do not forget it during your prayers; God, the angels and God's holy men listen to you.