Parshas Matos
“He may not break his word!” (Bamidbar 30:3)
It is a negative commandment that one may not change from that which we obligate ourselves with our speech even if it is not an oath. The following are examples of vows. If a man says that all of the fruit of the world or the fruit of a certain region or species are forbidden to him, these words take effect, and he is forbidden to eat those fruit. anything similar to this is also included and about this it says “He may not break his word!”, and Chazal explained that this means “He may not make his words profaned!”. Similarly, any time that a person vows to give something to beautify the temple or for an offering or for charity or a synagogue etc., if he does not fulfil his vow he transgresses this commandment. However, when it comes to other things, such as saying that he will do or not do a certain thing, without using the expressions reserved for vows etc., he does not transgress this commandment. It is however, to be avoided and is the type of thing that only coarse people do. About all of this the Torah says “Keep away from lies!”.
The root of this commandment regarding vows has already been explained.
Amongst the laws of this commandment are that which Chazal said a person cannot break his own oath, but a beis din of three people or a single expert can repeal the vow.
This commandment applies in all places and at all times, both to men and to women. One who vows and does not fulfil it has transgressed this commandment.
