Let us not then make ourselves unworthy of entrance into the bride-chamber: for as long as we are in this world, even if we commit countless sins it is possible to wash them all away by manifesting repentance for our offenses: but when once we have departed to the other world, even if we display the most earnest repentance it will be of no avail, not even if we gnash our teeth, beat our breasts, and utter innumerable calls for succor, no one with the tip of his finger will apply a drop to our burning bodies, but we shall only hear those words which the rich man heard in the parable ‘Between us and you a great gulf has been fixed.’ [Luke xvi. 26]
Let us then, I beseech you, recover our senses here and let us recognize our Master as He ought to be recognized. For only when we are in Hades should we abandon the hope derived from repentance: for there only is this remedy weak and unprofitable: but while we are here even if it is applied in old age itself it exhibits much strength. Wherefore also the devil sets everything in motion in order to root in us the reasoning which comes of despair: for he knows that if we repent even a little we shall not do this without some reward. But just as he who gives a cup of cold water has his recompense reserved for him, so also the man who has repented of the evils which he has done, even if he cannot exhibit the repentance which his offenses deserve, will have a commensurate reward. For not a single item of good, however small it may be, will be overlooked by the righteous judge. For if He makes such an exact scrutiny of our sins, as to require punishment for both our words and thoughts, much more will our good deeds, whether they be great or small, be reckoned to our credit at that day.
Wherefore, even if thou art not able to return again to the most exact state of discipline, yet if thou withdraw thyself in a slight degree at least from thy present disorder and excess, even this will not be impossible: only set thyself to the task at once, and open the entrance into the place of contest; but as long as thou tarriest outside this naturally seems difficult and impracticable to thee. [Matt. xxv. 34; 249 Luke xvi. 26]. For before making the trial even if things are easy and manageable they are wont to present an appearance of much difficulty to us: but when we are actually engaged in the trial, and making the venture the greater part of our distress is removed, and confidence taking the place of tremor and despair lessens the fear and increases the facility of operation, and makes our good hopes stronger.
For this reason also the wicked one dragged Judas out of this world lest he should make a fair beginning, and so return by means of repentance to the point from which he fell. For although it may seem a strange thing to say, I will not admit even that sin to be too great for the succor which is brought to us from repentance. Wherefore I pray and beseech you to banish all this Satanic mode of thinking from your soul, and to return to this state of salvation.
St. John Chrysostom, An Exhortation to Theodore After His Fall, Letter 1