The full and complete definition of repentance is that we never again allow in ourselves the sins of which we repent, or whereby our conscience is stung. The mark of satisfaction and forgiveness is when we have driven out from our hearts all desire for them.
First, one prays with the simplicity typical of beginners and by shedding copious tears. All this is due to the grace of God which is called purifying grace, which catches us like a fish-hook, and guides us towards repentance. For it is our God, Who is good in all and to all, Who finds us. He sees us. He invites Himself known to us first. Then we get to know Him, after He anoints us with His divine mercy. Hence, repentance, mourning, tears, and everything that happens to someone who repents, is all due to divine grace. This is purifying grace which cleanses man.
It is always possible to make a new start by means of repentance. 'You fell,' it is written, 'now arise'(cf. Prov. 24:16). And if you fall again, then rise again, without despairing at all of your salvation, no matter what happens. So long as you do not surrender yourself willingly to the enemy, your patient endurance, combined with self-reproach, will suffice for your salvation. 'For at one time we ourselves went astray in our folly and disobedience,' says St. Paul. '... Yet He saved us, not because of any good things we had done, but in His mercy' (Tit. 3:3,5).
Painstaking repentance, mourning cleansed of all impurity, and holy humility in beginners, are as different and distinct from each other as yeast and flour from bread. By open repentance the soul is broken and refined; it is brought to a certain unity, I will even say a commingling with God, by means of the water of genuine mourning. Then, kindled by the fire of the Lord, blessed humility becomes bread and is made firm without the leaven of pride. Therefore, when this holy three-fold cord or, rather, heavenly rainbow, unites into one power and activity, it acquires its own effects and properties. And whatever you name as an indication of one of them, is a token also of another. The first and paramount property of this excellent and admirable trinity is the acceptance of indignity with the greatest pleasure, when the soul receives it with outstretched hands and welcomes it as something that relieves and cauterizes diseases of the soul and great sins. The second property is the loss of all bad temper, and humility as its subsiding. The third and highest degree is a true distrust of one’s good qualities and a constant desire to learn.
Once when a hippopotamus was ravaging the neighboring countryside the fathers called on Abba Bes to help them. He stood at the place and waited and when he saw the beast, which was of enormous size, he commanded it not to ravage the countryside any more, saying, 'In the name of Jesus Christ, I order you not to ravage this countryside anymore.' The hippopotamus vanished completely from that district as if driven away by an angel.
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?
What does spoil repentance is being again entangled in the same evils. 'For there is one' we read, 'who builds, and one who pulls down, what have they gained more than toil? He who is dipped in water because of contact with a dead body, and then touches it again, what has he gained by his washing?' Even so if a man fasts because of his sins, and goes his way again, and does the same things, who will hear his prayer? And again we read 'if a man goes back from righteousness to sin the Lord will prepare him for the sword,' and, 'as a dog when he has returned to his vomit, and become odious, so is a fool who by his wickedness has returned to his sin.'
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.
When it is painful to remember the past, it is better to simply repent of what had been bad, and think no more about it. In order not to despair or be enfeebled by it, 'remember the examples of God's great mercies to great sinners. The main thing: do not condemn, do not envy, know yourself and be with God.'
You will not perish on account of thoughts with which you do not sympathize and from which you at least try to be freed. Only repent, & humble yourself. And God will forgive you.
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.
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.
Whoever repents sincerely is prepared to withstand any sorrow: hunger and homelessness, cold and heat, illness and poverty, humiliation and banishment, lies and slander, for the soul seeks God and does not concern itself with anything worldly, but instead prays with a clear mind.