Your enemy, the evil one, the father of lies, does not slumber; and endeavors, by every means open to him, to harden your heart --- to make it false and crafty, to drive out from it faith and hope in God - together with love for Him and love and sympathy for your neighbor - and to occupy you with worldly, temporal interests. Watch yourself, watch the thoughts of your heart, and do not bind yourself in the chains of worldly desires and pleasures. Let your happiness be in the one God and the human soul.
We must accomplish the course of our earthly pilgrimage with the greatest attention and watchfulness over ourselves, unceasingly calling upon God in prayer for help.
We must vigilantly guard our heart from unfitting thoughts and impressions, according to the word of the writer of Proverbs: ‘Keep thine heart with the utmost care; for out of these are the issues of life,’ (Proverbs 4:23).
Continually take careful note of your inner intention: watch carefully which way it inclines, and discover whether it is for God and the sake of goodness itself and the benefit of your soul...
Watch constantly, learning to understand God's law, for this warms the heart with heavenly fire. Guard your lips from the idle word, or empty talk, lest the heart gets used to evil words.
Let us go forward with the heart completely attentive and the soul fully conscious. For if attentiveness and prayer are daily joined together, they become like Elias' fire-bearing chariot, raising us to heaven. What do I mean? A spiritual heaven, with sun, moon and stars, is formed in the blessed heart of one who has reach a state of watchfulness, or who strives to attain it.
We should zealously cultivate watchfulness, my brethren; and when, our mind purified in Christ Jesus, we are exalted by the vision it confers, we should review our sins and our former life, so that shattered and humbled at the thought of them we may never lose the help of Jesus Christ our God in the invisible battle.
There is a sin which is always 'unto death' [1 Jn 5:16]; the sin which we have not repented. Even a saint's prayers will not be heard for the unrepented sin. The person who repents correctly does not imagine that his sins are cancelled through his own effort; but knows that through this effort he makes peace with God.
For never is a man forced into sin by another’s fault, unless he have, stowed away in his heart, matter for evil deeds. Nor is a man to be held a victim of sudden deception if at the sight of a woman’s beauty he fall into an abyss of vile lust. Rather is it that diseases of soul, deeply hidden away and lost to view, come then to the surface on the occasion of the sight.
No Christian believing rightly in God should ever be off his guard. He should always be on the look-out for temptation, so that when it comes he will not be surprised or disturbed, but will gladly endure the toil and affliction it causes, and so will understand what he is saying when he chants with the prophet: 'Prove me, O Lord, and try me' (Ps. 26:2 LXX). For the prophet did not say, 'Thy correction has destroyed me,' but, 'it has upheld me to the end' (Ps. 18:35 LXX).
It is vain that some unenlightened people seek the greatest evil for man somewhere else, rather than in sin. Some consider disease to be the greatest evil, others - poverty, and others - death. But neither disease, nor poverty, nor death, nor any other earthly disaster can be such a great evil for us as sin is. These earthly misfortunes do not separate us from God if we are seeking Him sincerely, but, on the contrary, they bring us closer to Him.
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.
A thick rope is composed of thin strands of hemp. One thin strand cannot hold you bound nor strangle you, for you will easily, with the lightest touch, break it and free yourself. But if a thick rope binds you, you will stay bound, and it will strangle you. You cannot easily break it and free yourself of it. As a thick rope is made from thin, weak strands, so men's passions are made up of smaller initial sins. The small, initial sins a man can still break and free himself of. But sin on sin, repeated, the weave becomes thicker and thicker until it becomes a passion, which masters a man as only it can do. You can neither cut it out easily nor cast it away from you nor be divorced from it. Oh, when will men guard themselves from these first sins? Then they would not have so much difficulty in freeing themselves from the passions.