The tongue as a sword and the law against oaths

Let us think the same way about the tongue. It is a sword lying in the middle. Sharpen it, then, against the accusation of your own sins, but do not thrust the blow against a brother. For this reason God surrounded it with a double wall—the barrier of the teeth and the enclosure of the lips—so that it may not easily and thoughtlessly utter words that are not fitting. Bridle it within. But it will not submit? Then discipline it with your teeth, as if handing over its body to these executioners and making it bite itself. For it is better for the tongue to be bitten by the teeth now while it is sinning, than to seek a drop of water then, while being roasted, and not obtain that comfort.

The tongue is accustomed to commit many other sins as well: insulting, blaspheming, uttering shameful words, slandering, swearing oaths, committing perjury. But so that we do not bury your mind today by telling you everything at once, we lay down for you for the present one law, the law about guarding against oaths. And we declare and announce this in advance: if you do not flee from oaths—I do not mean only perjury, but even oaths made for a just cause—if you do not flee from them, we will no longer discuss any other subject with you. For it would be absurd if teachers of letters do not give children a second lesson until they see the first one firmly fixed in their memory, but we, unable to deliver the earlier lessons with accuracy, pile on others again. That is nothing other than drawing water from a pierced jar.

So that you may not stop our mouths, make every effort in this matter. For this sin is difficult, exceedingly difficult. And it is exceedingly difficult because it does not seem difficult. This is why I fear it—because no one fears it. This is why the disease is incurable—because it does not even seem to be a disease. Just as ordinary conversation is not a crime, so this does not seem to be a crime either, but this lawlessness is committed with great boldness. And if someone rebukes it, immediately there follows laughter and much mockery—not against those who bring charges concerning oaths, but against those who want to correct the disease. For this reason I stretch out my discourse at length about these things. I want to pull up a deep root and wipe away a long-standing evil. I do not mean only perjury, but even truthful oaths themselves.

But someone says, “That man is decent, he is enrolled for the priesthood, he lives with great self-control and piety.” Do not tell me about this decent man, this self-controlled man, this pious man, this man enrolled for the priesthood. If you wish, suppose that he is Peter or Paul, or even an angel come down from heaven. Even so I do not turn toward the dignity of persons. For the law I read about oaths is not a slave’s law but a king’s law. And when a king’s letters are read, let all the dignity of slaves be silent. If you can say that Christ commanded us to swear, or that Christ does not punish this when it happens, show me and I am persuaded. But if he forbids it with such earnestness and shows such care for the matter that he places the one who swears alongside the Evil One—for “anything more than these, than yes and no,” he says, “is from the devil” (Matthew 5:37)—why do you bring this man or that man into the discussion? God will not render his verdict to you based on the negligence of your fellow servants, but based on the command of his own laws.