על עשרת הדברות י״טOn the Decalogue 19
א׳
1[92] There are some who without even any gain in prospect have an evil habit of swearing incessantly and thoughtlessly about ordinary matters where there is nothing at all in dispute, filling up the gaps in their talk with oaths, forgetting that it were better to submit to have their words cut short or rather to be silenced altogether, for from much swearing springs false swearing and impiety.
ב׳
2[93] Therefore one who is about to take an oath should have made a careful and most punctilious examination, first of the matter in question, whether it is of sufficient importance, whether it has actually happened, and whether he has a sound apprehension of the facts; secondly, of himself, whether his soul is pure from lawlessness, his body from pollution, his tongue from evil-speaking, for it would be sacrilege to employ the mouth by which one pronounces the holiest of all names, to utter any words of shame.
ג׳
3[94] And let him seek for a suitable time and place. For I know full well that there are persons who, in profane and impure places where it would not be fitting to mention either a father or mother or even any good-living elder outside his family, swear at length and make whole speeches consisting of a string of oaths and thus, by their misuse of the many forms of the divine name in places where they ought not to do so, show their impiety.
ד׳
4[95] Anyone who treats what I have said with contempt may rest assured, first, that he is polluted and unclean, secondly, that the heaviest punishments are waiting to fall upon him. For justice, who surveys human affairs, is inflexible and implacable towards such grave misdeeds, and when she thinks well to refrain from immediate chastisement, be sure that she does but put out her penalties to loan at high interest, only to exact them when the time comes to the common benefit of all.