Those who fervently desire to remain amid (in the world) as well as those who live a worthy life in communities, in mountains and in caves are saved; and God bestows on them great blessings solely because they rest their faith in Him.
The soul of all practices in the Lord is vigilance. Without vigilance, all these practices are fruitless. He who is desirous of saving himself must so establish himself that he might remain continuously vigilant toward himself, not only in solitude, but also under conditions of distraction, into which he is sometimes unwillingly drawn by circumstances.
Apostolic teaching, Beloved, exhorts us that we put off the old man with his deeds (Eph. iv. 22; Col. iii. 9), and renew ourselves from day to day by a holy manner of life. For if we are the temple of God, and if the Holy Spirit is a Dweller in our souls, as the Apostle says: You are the temple of the living God (II Cor. vi. 16); we must then strive with all vigilance that the dwelling of our heart be not unworthy of so great a Guest.
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).
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).
It is impossible for the soul to attain anything spiritual and pleasing to God, or to be free of inner sin, without guarding of the mind and purity of heart, in other words, without sobriety... If with God's help we gain something daily through our sobriety, we should take care not to enter into communication with other people without discrimination, lest we suffer loss through our converse with them and are led into temptation.
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.
A monk is he who wants to sleep and does not sleep, who wants to eat and does not eat, who wants to drink and does not drink. A monk is distinguished by ‘continual forcing of nature.’
And the old man also said, 'God saith unto thee thus -- if thou lovest Me, O monk, do that which I ask, and do not that which I do not desire. For monks should lead lives wherein they act not in iniquity, and a man should not look upon evil things with his eyes, no hear with his ears things which are alien to the fear of God, nor utter calumnies with his mouth, nor plunder with his hands; but he should give especially to the poor, and he should not be unduly exalted in his mind, and he should not think evil thoughts, neither should he fill his belly. Let him do then all these things with discretion, for by them is a monk known.' The old man also said, 'These things form the life of a monk: good works, and obedience, and training. A man should not lay blame on his neighbor, and he should not utter calumnies, and he should not complain, for it is written, 'The lovers of the Lord hate wickedness.'
Angels are a light for monks, and the monastic life is a light for all men. Therefore let monks strive to become a good example in everything, giving no occasion for stumbling in anything (II Corinthians 6:3) in all their works and words. For if the light becomes darkness, how much darker will be that darkness, that is, those living in the world.
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.
Monasticism itself is a perpetual labor of conquering passions and uprooting them in order that, being in a pure and immaculate state, one may preserve oneself before the face of God. This, then, is your task! Give your attention to it, and direct all your powers towards it.
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.
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.