9 But unto those who are seized by it and broken down, if they will consent to put themselves into the hands of the Word of healing, I promise large hope of salvation, by the Grace of God. For if they will consider those who have suffered and fallen into that distemper and have recovered, they will have good hopes respecting the removal of the disease. Who then ever fell into this disease, and was easily rid of it? That well-known Zacchæus. For who could be more fond of money than a publican? But all at once he became a man of strict life, (Φιλόσοφος) and put out all that blaze. Matthew in like manner: for he too was a publican, living in continual rapine. But he likewise all at once stripped himself of the mischief, and quenched his thirst, and followed after spiritual gain. Considering therefore these, and the like to them, despair not even thou. For if you will, quickly you shall be able to recover. And if you please, according to the rule of physicians, we will prescribe accurately what you should do.
It is necessary then, before all other things, to be right in this, that we never despond, nor despair of our salvation. Next, we must look not only upon the examples of those who have done well, but also upon the sufferings of those who have persisted in sin. For as we have considered Zacchæus, and Matthew, even so ought we also to take account of Judas, and Gehazi, and Ahar, [perhaps Achan, Josh. vii.] and Ahab, and Ananias, and Sapphira, in order that by the one, we may cast out all despair, and by the other cut off all indolence; and that the soul become not reckless of the remedies suggested. And let us teach them of themselves to say what the Jews said on that day, approaching unto Peter, “What must we do to be saved?” And let them hear what they must do.
Source: Homilies on First Corinthians (New Advent)