On Idolatry by Tertullian
Chapter XXIII.--Written Contracts in the Name of Idols. Tacit Consent.
But there is a certain species of that class, doubly sharpened in deed and word, and mischievous on either side, although it flatter you, as if it were free of danger in each; while it does not seem to be a deed, because it is not laid hold of as a word. In borrowing money from heathens under pledged securities, Christians give a guarantee under oath, and deny themselves to have done so. Of course, the time of the prosecution, and the place of the judgment seat, and the person of the presiding judge, decide that they knew themselves to have so done. Christ prescribes that there is to be no swearing. |I wrote,| says the debtor, |but I said nothing. It is the tongue, not the written letter, which kills.| Here I call Nature and Conscience as my witnesses: Nature, because even if the tongue in dictating remains motionless and quiet, the hand can write nothing which the soul has not dictated; albeit even to the tongue itself the soul may have dictated either something conceived by itself, or else something delivered by another. Now, lest it be said, |Another dictated,| I here appeal to Conscience whether, what another dictated, the soul entertains, and transmits unto the hand, whether with the concomitance or the inaction of the tongue. Enough, that the Lord has said faults are committed in the mind and the conscience. If concupiscence or malice have ascended into a man's heart, He saith it is held as a deed. You therefore have given a guarantee; which clearly has |ascended into your heart,| which you can neither contend you were ignorant of nor unwilling; for when you gave the guarantee, you knew that you did it; when you knew, of course you were willing: you did it as well in act as in thought; nor can you by the lighter charge exclude the heavier, so as to say that it is clearly rendered false, by giving a guarantee for what you do not actually perform. |Yet I have not denied, because I have not sworn.| But you have sworn, since, even if you had done no such thing, you would still be said to swear, if you have even consented to so doing. Silence of voice is an unavailing plea in a case of writing; and muteness of sound in a case of letters. For Zacharias, when punished with a temporary privation of voice, holds colloquy with his mind, and, passing by his bootless tongue, with the help of his hands dictates from his heart, and without his mouth pronounces the name of his son. Thus, in his pen there speaks a hand clearer than every sound, in his waxen tablet there is heard a letter more vocal that every mouth. Inquire whether a man have spoken who is understood to have spoken. Pray we the Lord that no necessity for that kind of contract may ever encompass us; and if it should so fall out, may He give our brethren the means of helping us, or give us constancy to break off all such necessity, lest those denying letters, the substitutes for our mouth, be brought forward against us in the day of judgment, sealed with the seals, not now of witnesses, but of angels!