To wage war only with the sins that make their appearance as actual deeds would be just as unsuccessful as cutting down weeds in a garden instead of digging them up at the root and throwing them out. Sins appear as inevitable outgrowths from their roots, the passions of the soul.
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.
The enemy of our salvation especially strives to draw our heart and mind away from God when we are about to serve Him, and endeavors 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.
But where does Christ dwell? In pure hearts, hearts that are humble and contrite, there where He is not grieved by doubt or unbelief, by indifference towards Him, Who is God and Savior; there where men do not prefer the temporal sweetness of sin; where the idols of the passions have been chased out; where crude materiality is not preferred to the Kingdom of God, where Christians often turn their thoughts to the heavenly, as those created for heaven, for eternity; there where they seek God's truth, where every day and every hour they are attentive to His commandments. Here is where Christ dwells. And what does He do there? If only we knew (some, of course, do know) what He does in souls worthy of His abiding presence--what rest, comfort and joy He imparts, what paradisical bliss He gives them to experience while still on this earth.
Ask the angels and the saints to intercede for you, just as you'd ask people who are alive. Stand face to face with them, in the belief that they are also standing face to face with you.
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.
Imagine, picture the multitude of your sins and imagine how tolerant of them is the Master of your life, while you are unwilling to forgive your neighbor even the smallest offense. Moan and bewail your foolishness, and that obstruction within you will vanish like smoke, you will think more clearly, your heart will grow calm, and through this you will learn goodness, as if not you yourself had heard the reproaches and indignities, but some other person entirely, or a shadow of yourself.
Sometimes we do not see any outlet, any escape from our sins, and they torment us: on account of them, the heart is oppressed with sorrow and weary. But Jesus looks upon us, and streams of tears flow from our eyes, and with the tears all the tissue of evil in our soul vanishes. We weep with joy that such mercy has suddenly and unexpectedly been sent to us.
Both public and private prayer are necessary in order that we may lead a truly Christian life, and that the life of the spirit should not become extinct in us. It is indispensable that we should attend divine service in church with faith, zeal and understanding, just as it is indispensable to provide a lamp with fuel or power if it is to burn and not to go out.
The truth and saving properties of our holy faith are clearly revealed by the fact that not a single Sacrament, not a single faithful prayer are left fruitless in us, but they bring and manifest their power from heaven upon our souls and bodies, cleansing our sins, and giving peace to our souls in accordance with the words of our Savior: 'Come unto Me, all ye that labor and are heavy laden, and I will give you rest' (Mt. 11:28); and delivering us from spiritual afflictions and bodily sicknesses! No, we never pray in vain to the Lord, or to the most holy Virgin, or to the angels and saints, but we receive all that we ask them for, and that tends to our salvation.
To what end do fasting and penitence lead? For what purpose is this trouble taken? They lead to the cleansing of the soul from sins, to peace of heart, to union with God; they fill us with devotion and sonship, and give us boldness before God.