23 These things I now speak to you, not as if reproving you for your own sins, but for the sake of others; for I know full well that by you (as I have already observed), this law concerning swearing has been accomplished. But this does not suffice for our safety, unless by teaching we amend others, since he who produced the one talent, restoring as he did the whole portion committed to him, was punished, because he had not enriched that with which he was entrusted. Wherefore, let us not regard this point, that we ourselves have been set free from this sin; but until we have delivered others from it, let us not desist; and let every one offer to God ten friends whom he has corrected; whether you have servants, or apprentices: or if you have neither servants, nor apprentices, you have friends; these do thou reform.
Further, do not make me this reply; “We have banished oaths for the most part, and we are rarely caught in that snare;” but let even this rarity of offending be got rid of. If you had lost one piece of gold, would you not go about to all persons, searching and making enquiry, in order to find it? This do also with regard to oaths. If you perceive that you have been cheated out of one oath, weep, lament, as though your whole substance were lost. Again I say what I did before. Shut up yourself at home; make it a subject of practice and exercise along with your wife, your children, and domestics.
Say to yourself in the first instance, “I must not put a finger to private or public matters until I have rectified this soul of mine.” If you will thus school your own sons, they too will instruct their children in turn, and thus this discipline, reaching even to the consummation and appearing of Christ, will bring all that great reward to those who go to the root of the matter. If your son has learned to say, “Believe me;” he will not be able to go up to the theatre, or to enter a tavern, or to spend his time at dice; for that word, lying upon his mouth instead of a bridle, will make him however unwilling feel shame and blush.
But if at any time he should appear in these places, it will quickly compel him to retreat. Suppose some persons laugh. Do thou on the other hand weep for their transgression! Many also once laughed at Noah while he was preparing the ark; but when the flood came, he laughed at them; or rather, the just man never laughed at them at all, but wept and bewailed! When therefore you see persons laughing, reflect that those teeth, that grin now, will one day have to sustain that most dreadful wailing and gnashing, and that they will remember this same laugh on That Day while they are grinding and gnashing! Then thou too shall remember this laugh! How did the rich man laugh at Lazarus! But afterwards, when he beheld him in Abraham's bosom, he had nothing left to do but to bewail himself!
Source: Homilies on the Statues (New Advent)