Sorrow over your sins makes you as gentle and meek as a lamb; and where there is meekness and gentleness, there is serenity and beatitude. What is more precious and blessed than spiritual calm?
Repentance is real when afterwards you keep trying strenuously to live now as you ought; but without this it is not very effectual, if you repent just to say your sins & to keep on living as before.
A man who falls into sin is different from the way he was created. He is different, because he changes by his own actions the way he was meant to be. Man renounces himself when he becomes a different person through repentance. He leaves a corrupted man, which he had become through sin, and becomes such as he once was created, through mercy.
In words of boastfulness and self-justification there always lie concealed contrariness and pride, from which God turns away. After sinning one ought immediately to 'flee.' But, you will say, where? To the calm haven of heartfelt repentance. Every night before you go to sleep, tell God, the Knower of Hearts, all the sins you have committed in deed, word, and thought, and believe that God receives your heartfelt repentance. At the same time try to render your heart contrite by the memory of sudden death.
A person lighting a fire first has a small piece of tinder. This represents the word of the brother who has upset him. This little fire is very feeble. What significance has the word of your brother? If you put up with it you blow out the small fire, but if you begin to think to yourself, 'Why did he say that to me? I myself can answer him. If he did not want to hurt me, he wouldn't have said that and believe me, I can upset him too.' In this case, you add small pieces of wood to the fire and some other fuel like the person that lights a fire and you produce smoke which is agitation. Agitation is the movement and coming together of thoughts which stimulate the heart and make it audacious. Audacity is the taking of retribution against the person that has upset you, and this becomes insolence as Abba Mark said, 'Evil accepted in thought makes the heart audacious, but when this is revoked through prayer and hope, it makes it contrite.'
This day the earth became Heaven for us. Not because the stars descended from the heavens to earth, but because the apostles ascended to Heaven by the grace of the Holy Spirit, which was now abundantly poured forth, and so the whole world was transformed into heaven; not because human nature was changed, but because there was a change in the direction of the will. For there was found a tax-gatherer, and he was transformed into an evangelist. There was found a persecutor, and he was changed into an apostle. There was found a robber, and he was led into Paradise. There was found a prostitute, and she was made the equal of virgins. There were found wise men, and they were taught the Gospels. Evil fled away, and gentleness took its place. Slavery was put away, and freedom came in its stead. And all debts were forgiven, and the grace of God was conferred. Therefore Heaven became earth.
The grace of repentance, which acts in those who struggle, is a patristic inheritance. It is a divine transaction and exchange in which we give dust and receive heaven. We exchange matter for the Spirit. Every drop of sweat, every pain, every ascesis for God is an exchange.
If Moses, who was a god to Pharaoh, was shut out from the Land of Promise because of one word, how much more will not the evil speech of our tongue, by which we offend and hurt both God and man, shut us out from heaven?
If we remember the thief who, for a single confession on the cross, was taken into Paradise, we shall realize that it was not for the merit of the life he lived that he obtained so great blessedness, but that it was his by the gift of God, Who had mercy on him. Or, let us think of David, the king, whose two grievous and awful crimes were wiped away by one word of penitence. Neither here do we see that the merit of what he did was equal to obtaining pardon for such great offense, but the grace of God did the more abound when on the occasion of true penitence He did away with all that weight of sin for one single word of genuine confession. Again, when we consider the beginnings of man's calling and salvation, which, as the Apostle tells us, is not of ourselves or of our words, but we are saved by the gift and grace of God, we shall be able clearly to perceive how the end of perfection is not 'of him that willeth, nor of him that runneth, but of God Who showeth mercy,' Who makes us victors over our vices, although we have no merit at all of life or labors to weigh against them, nor does the effort of our will avail for us to reach the steep summit of righteousness, or to subdue the flesh which we are bound to use... For the outcome of all good flows from His grace, Who hath bestowed so great an eternity of bliss and such immeasurable glory, with manifold generosity, upon the weak will and the short life-work of man.
But if you are fearful of becoming self-righteous from working for your own salvation, or afraid of being overcome by spiritual pride, examine yourself and observe that the person who is afraid of becoming self-righteous suffers from blindness. For he does not see how self-righteous he is.
The Lord commands all men to repent (Matt. 4:17), so that even the spiritual and those making progress should not neglect this injunction and fail to give attention to the smallest and most subtle errors.
If the main goal of the repentant sinner should be total, light-bearing and blessed communion with God, then the main hindrance to this is the existence of the passions still active and working in him - the virtues being as yet unsealed in him - and the unrighteousness of his powers. Therefore his main work upon conversion and repentance should be the uprooting of the passions and sealing the virtues - in a word, correcting himself.
By holy baptism original sin is expunged, as also sins committed before baptism. It also eliminates the violent power sin has over us till rebirth; it gives us the grace of the Holy Spirit by which we are united with God in Christ, and we receive power to subdue and conquer sin. For the simple reason that we are not delivered from the struggle with sin, we cannot be entirely free from sin during the whole of our earthly life, and even the righteous man may fall seven times (i.e. often) and rise again by repentance, says Scripture (Prov. 24:16). He falls on account of his weakness and limitations, because he does not always notice sin which subtly and imperceptibly rears its head from his fallen nature, and which is artfully and imperceptibly offered and suggested by fallen spirits. Repentance becomes his secure possession, his constant weapon, his invaluable treasure. By repentance the righteous man maintains his fellowship with Christ. He is healed by repentance from the wounds caused by sin.