Let us then hold fast to virtue; let not these words end only in delight, and in a certain elevation of the spirits. This is not the theatre, for singers (κιθαρώδων), and tragedians, and musicians (κιθαριστὥν), where the fruit consists only in the enjoyment and where the enjoyment itself passes with the passing day. Nay, would that it were enjoyment alone, and not mischief also with the enjoyment! But so it is: each man carries home with him much of what he has witnessed there, sticking to him like the infection of a plague: and one indeed, of the younger sort, having culled such snatches of song here and there of those satanic plays, as he could fix in his memory, goes singing them about the house: while another, a senior, and forsooth too staid for such levity, does not this indeed, but what is there spoken, both the preachments and the very words, he remembers it all; and another again, some filthy and absurd ditty.
From this place you depart, taking nothing with you.— We have laid down a law— nay, not we: God forbid! For it is said, “Call no man your master upon the earth”; Christ has laid down a law that none should swear. Now, say, what has been done with regard to this law? For I will not cease speaking of it; “lest,” as the Apostle says, “if I come again, I must not spare.” I ask then, have you laid the matter to heart? Have you thought of it seriously? Have you been in earnest about it, or must we again take up the same subject?
Nay, rather, whether you have or not, we will resume it, that you may think seriously about it, or, if you have laid it to heart, may again do this the more surely, and exhort others also. With what then, I pray you, with what shall we begin? Shall it be with the Old Testament? For indeed this also is to our shame, that the precepts of the Law, which we ought to surpass, we do not even thus observe! For we ought not to be hearing such matters as these: these are precepts adapted to the poor Jewish level (τἥς ᾿Ιουδαἲκἥς εὐτελείας): we ought to be hearing those counsels of perfection; “Cast away your property, stand courageously, and give up your life in behalf of the Gospel, scorn all the goods of earth, have nothing in common with this present life; if any wrong you, do him good; if any defraud you, bless him; if any revile you, show him honor; be above everything.”
(S. Ambros. de Off. i. 2.) These and such as these are what we ought to be hearing. But here are we discoursing about swearing; and our case is just the same as if, when a person ought to be a philosopher, one should take him away from the great masters, and set him to spell syllables letter by letter! Just think now what a disgrace it would be for a man having a flowing beard, and with staff in hand, and cope on shoulders, to go to school with children, and be set the same tasks with them: would it not be above measure ridiculous?
And yet the ridicule which belongs to us is even greater. For not as the difference between philosophy and the spelling-lesson, so is that between the Jewish polity and ours: no indeed, but as the difference between angels and men. Say now, if one could fetch down an angel from heaven, and should bid him stand here and listen to our preaching, as one whose duty it is to conform himself thereto, would it not be shameful and preposterous? But if to be yet, like children, under teaching about these things be ridiculous; what must it be, not even to attend to these things: how great the condemnation, how great the shame! To be Christians still, and to have to learn that it is not right to swear! However, let us put up with that, lest we incur even worse ridicule.
Source: Homilies on Acts (New Advent)