Any soul which has lost its peace must repent, and the Lord will forgive its sins, and then peace and joy will visit the soul. There need be no witnesses, for the Holy Spirit is the witness of the remission of sins. Here is a sign of forgiveness: if you have come to hate sin, then the Lord has forgiven your sin.
This prayer should never be absent from you: 'Lord Jesus Christ, Son and Logos of the living God, through the Theotokos and all the Saints, have mercy upon me, Thy sinful and unworthy servant.' (This is the actual Jesus Prayer: 'O LORD JESUS CHRIST, SON OF GOD, HAVE MERCY UPON ME, A SINNER.') Always say this prayer both with your mouth and with your mind, day and night, wherever you may be, whether eating, walking, working, or sitting. Always meditate on it, as it benefits you a great deal, frees you here from every evil, delivers you there from eternal Hell, and renders you worthy of going to Paradise, our heavenly country.
We must always pray to the Lord to tell us what to do, and the Lord will not let us go astray. Adam was not wise enough to ask the Lord about the fruit which Eve gave him, and so he lost paradise. David did not ask the Lord whether it would be a good thing if he took Beth-sheba to wife, and so he fell into the sins of murder and adultery. So with all the saints who sinned: they sinned because they had not called upon God to enlighten and help them. St. Seraphim of Sarov said, ‘When I spoke of myself I was often in error.’
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).
We ought to learn the virtues through practicing them, not merely through talking about them, so that by acquiring the habit of them we do not forget what is of benefit to us.
St. John Climacus was asked if there are reliable signs by which it's possible to know whether a soul is drawing near to God or moving away from Him. After all, regarding ordinary things there are clear signs as to whether they're good or not. When, for instance, cabbage, meat or fish begins to rot, it's easy to notice it, since the rotting object begins to give off a foul odor, the color and taste change, and its external appearance witnesses to its deterioration. Well, and what about the soul? After all, it's bodiless and can't give off a bad smell or change its appearance. To this question the Holy Father replies, 'A sure sign of the deadening of the soul is the avoidance of church services.'
When despondency seizes us, let us not give in to it. Rather, fortified and protected by the light of faith, let us with great courage say to the spirit of evil: 'What are you to us, you who are cut off from God, a fugitive for Heaven, and a slave of evil? You dare not do anything to us: Christ, the Son of God, has dominion over us and over all. Leave us, you thing of bane. We are made steadfast by the uprightness of His Cross. Serpent, we trample on your head.'
When the Spirit of God comes down to man and overflows him with the fullness of His inspiration, then the human soul overflows with unspeakable joy, for the spirit of God fills with joy whatever He touches.
There is nothing more efficacious against the wiles of the devil, dearly beloved, than the kindness of forgiveness, and the bountifulness in charity, by means of which sin is either avoided or overcome.
God's all-saving will consists in doing good solely to acquire the Holy Spirit, as an eternal, inexhaustible treasure which cannot be rightly valued... This is the oil in the lamps of the wise virgins which could burn long and brightly, and these virgins with their burning lamps were able to meet the Bridegroom Who came at midnight, and could enter the bridechamber of joy with Him. But the foolish ones, though they went to market to buy some oil when they saw their lamps going out, were unable to return in time, for the door was already shut. The market is our life; the door of the bridechamber which was shut and which barred the way to the Bridegroom is human death; the wise and foolish virgins are Christian souls; the oil is not good deeds but the grace of the All-Holy Spirit of God which is obtained through them and which changes souls from one state to another - that is, from corruption to incorruption, from spiritual death to spiritual life, from darkness to light, from the stable of our being (where the passions are tied up like dumb animals and wild beasts) into a temple of the Divinity, into the shining bridechamber of eternal joy in Christ Jesus our Lord, the Creator and Redeemer and eternal Bridegroom of our souls.
God the Word, the God-Man, our Lord Jesus Christ, compares our life with a market, and the work of our life on earth He calls trading, and says to us all: Trade till I come (Luke 19:13), redeeming the time, because the days are evil (Ephesians 5:16). That is to say, make the most of your time for getting heavenly blessings through earthly goods. Earthly goods are good works done for Christ's sake and conferring on us the grace of the All-Holy Spirit.
'Lord Jesus Christ, Son of God, have mercy on me, a sinner.' Let your attention and instruction be centered on this. Walking, eating, standing in church before the beginning of the service, continue with the prayer; on entering and departing keep this prayer on your lips and within your heart. In such a manner, with the invocation of the Name of God you will find peace, you will attain to purity of spirit and body; and the Holy Spirit, the Origin of all good, will make for Himself a dwelling within you and will guide you in all piety and purity.
In patience is the assembly of all the virtues by which our souls are saved, as St. Ephraim says: having acquired patience, one touches on every virtue; for one rejoices in sorrows, and is well-tried in misfortunes, is joyful in danger, ready for obedience, filled with love, glories in vexation, is humbled in reproaches, unwavering in misfortunes; he who has acquired patience has acquired hope, and such a one is adorned with every good work.
Obedience is necessary not only for monks, but for all people. Even the Lord was obedient. Proud and self-assured do not let grace reside within them, and therefore they never have internal peace, whereas the soul of the obedient easily accepts the grace of the Holy Spirit, bringing with it joy and serenity.