579. Unintentional Acts of Labor

Shabbos 1:4

When we are told that something is permitted, the meaning is that one may perform such an act on Shabbos. Similarly, the expressions “not liable at all” and “completely exempt” mean that one receives no punishment whatsoever for performing the act in question.

Shabbos 1:5

One may perform a permitted act on Shabbos even if it is possible that a forbidden labor will be performed so long as it is not an absolute certainty that the labor will occur and one does not have the intention to perform the labor. For example, one may drag a bed, chair, or bench on the ground on Shabbos as long as he does not intend to carve ruts in the earth through his actions. Therefore, even if he did carve such ruts in the ground, it doesn’t matter since it was unintentional. Similarly, one may walk on grass on Shabbos as long as he does not intend to uproot it. If it should happen to be uprooted, it doesn’t matter. Similarly, one may rub herbs on his hands so long as he does not intend to remove the hair. Therefore, if the hair should happen to be removed, it doesn’t matter. One may likewise enter through a narrow opening on Shabbos even though he may cause pieces of masonry to fall. One may perform any such act as long as he does not intend any labor that may result.