The lives of men are subject to drastic changes. These changes are gradual at times; at others, lightning quick. But even those of us who enjoy long years of opulence and fame can find no consolation, no gladness, unless our heart is illumined by the steady light of peace. It is this peace that we must seek, it is for this peace that we should pray. The peace that our Lord gave to His disciples and to all those who really have faith in him.
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).
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.
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.
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).
Watchfulness cleanses the conscience and makes it lucid. Thus cleansed, it immediately shines like a light that has been uncovered, banishing such darkness. Once this darkness has been banished through constant and genuine watchfulness, the conscience then reveals things hidden from us.
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...
I shall indicate to you the most direct and simple method to acquire the habit of silence: ...reflect as often as you can on the pernicious results of indiscriminate babbling and on the salutary results of wise silence. When you come to taste the good fruit of silence, you will no longer need lessons about it.
If you are praised, be silent. If you are scolded, be silent. If you incur losses, be silent. If you receive profit, be silent. If you are satiated, be silent. If you are hungry, also be silent. And do not be afraid that there will be no fruit when all dies down; there will be! Not everything will die down. Energy will appear; and what energy!
If the saints, who had attained passionlessless, had to be vigilant over themselves so as not to fall from their state of grace - then all the more is daily attentiveness and concern over our eternal salvation necessary for us sinners. The fact that we are still alive means that the Lord patiently endures our sins and awaits our amendment, and if someone lawfully labors for his salvation, the Lord takes him at a time when he becomes worthy of God’s mercy.
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.
When someone is beginning the spiritual life, he should not study a lot, but instead watch himself and guard his thoughts. A strong person is the one who chews well, not the one who eats a lot.
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.