레위기 15:25 할라카: Gray Matter II, Mishneh Torah, Reading the Shema, Mishneh Torah, Rest & Sefer HaChinukh

In order to understand the problem, we must first define the Biblical concepts of nidah and zavah.³For a full introduction to these concepts, see Rav Pinchas Kehati’s commentary to the Mishnah (Arachin 2:1) and Badei Hashulchan (Introduction to 183). Nidah refers to a woman who sees menstrual blood on a day when she expects it to flow (Vayikra 15:19). This flow renders her ritually impure and prohibits relations with her husband for seven days. Even if she continues to see blood all seven days, she may go to the mikvah and purify herself immediately after they end. On the other hand, if a woman sees uterine blood at an unexpected time, then she becomes a zavah. If the bleeding persists for three consecutive days, she must wait until all bleeding ceases. She then counts seven days before she may visit the mikvah (Vayikra 15:25-28). Thus, once a zavah sees blood for three consecutive days, the total time that she remains impure will always last at least three days longer than the seven-day nidah period.

All who are ritually unclean are bound nevertheless to read the Shema; and, while still unclean, they recite the blessings that precede and succeed it, even if it is possible for them to get rid of their uncleanness, on the same day; as is the case with those who have touched a creeping thing, or touched a woman in the period of menstruation, or touched one who has a running issue, or the couch on which anyone of these has lain, etc. Ezra and his colleagues ordained that only one who had had an emission—as an exception to all unclean classes—may not read the words of the Torah till he has ritually bathed. This ordinance was not adopted universally. The majority of the community were unable to observe it, and it fell into desuetude. All Israelites have accordingly had the custom to read the Torah and recite the Shema, notwithstanding that they had had emissions. For the words of the Torah are insusceptible of defilement, but remain always pure, as it is said, "Is it not thus, my words are like fire, saith the Lord" (Jeremiah 23:29). Even as fire is incapable of being defiled, so the words of the Torah are insusceptible of defilement, but keep their purity forever.

Zavim; zavot; menstruants; women who have just given birth; and all others who leave a state of ritual impurity for a state of ritual purity in the middle of the festival—these are surely permitted to launder their clothing. And one who only has one cloak—such a one can surely launder it on the festival. Hand towels; barbers’ towels; and body-drying towels—these may surely be laundered on the festival. And likewise may we launder linen garments on the festival—as they need constant laundering, even if they were laundered on the eve of the holiday.