The Mishna on today’s daf continues the discussion of ketamim which do not render a woman to be ritually unclean on a biblical level although according to the rabbinic ruling a woman who finds a ketem on her clothing must behave as if she is a nidda (see daf 53). The Mishna relates the following ruling:
If three women slept in a single bed and blood was found under one of them, they are all unclean. If one of them examined herself and was found to be unclean, she alone is unclean while the two others are clean.
We have already learned that the Sages tried to be lenient with regard to ketamim, since they are only rabbinic in nature (see daf 58). This helps us understand why if one of the three women was found to be unclean, the others can assume that the bloodstain was hers and not theirs. Nevertheless, many commentators ask why in the first case of the Mishna any of them should be deemed unclean. The general principle of the Sages is that, “Safek tumah be-reshut ha-rabbim, tahor” – doubtful impurity in a public place is considered ritually pure – and that a reshut ha-rabbim is defined as a place with at least three people. Based on these principles, the three women should constitute a public place, and the questionable ketem should be treated leniently for all.
Many answers are offered to this question, among them:
- Three people do not always constitute a reshut ha-rabbim. If three people are in a hidden place – as is the case of three women in a bed – that would still be considered a private domain.
- The rule that doubtful impurity in a public place is considered ritually pure only applies when the impurity comes from the outside (e.g., we are unsure whether someone stepped over a grave), but does not apply when the impurity stems from the people themselves, as in the case of a ketem.
- Had the women presented their cases separately we may have applied these rules and declared them all pure. The situation, however, is where they all came together and we are forced to admit that any one of them could be the source of the ketem, so they are all declared ritually unclean.