§ The Sages taught in a baraita: In the case of a woman who saw a red stain on her garment, and afterward saw blood, what is the halakha? She attributes her stain to her seeing blood, i.e., the stain is treated as part of the seeing of blood, which means that she is impure only from when she found the stain, as it assumed that it appeared no earlier. This is the halakha provided that she saw the blood within a twenty-four-hour period of her discovery of the stain. But if more than twenty-four hours passed, she cannot attribute the stain to her sighting. This is the statement of Rabbi Yehuda HaNasi.
When a woman discovers a stain and then discovers bleeding, she associates the stain with the bleeding for a 24-hour period. [This applies] whether she inspected herself at the time she discovered the stain and found herself to be pure or whether she did not inspect herself. If, however, she discovers one stain after another stain within 24 hours, she does not associate one stain with the other unless she carried out an inspection in the interim. If, however, she carried out an inspection and found herself to be pure between [the discovery of the first] stain and the second, they should not be associated with regard to the counting of zivut.
The Gemara again answers: How can these cases be compared? There, in the case of the wine, it can be said that it was continuously turning to vinegar. Therefore, it is possible that the wine turned to vinegar much earlier without anyone realizing. By contrast, in the case of the menstruating woman, can it be said that she was continuously seeing menstrual blood? Once again, the Gemara responds: And what is the difficulty? The same possibility does in fact exist in the case of a menstruating woman, as perhaps she saw the blood depart bit by bit.
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Une tache trouvée comme il a été vu précédemment ne doit pas être considérée comme fixant une date de menstruation, et n’oblige à aucune précaution à la même époque pour le mois suivant. Ces taches, on l’a vu également, n’entraînent pas toujours la nécessité de la purification. Cependant la tache qui est trouvée sur le linge d’inspection demande toujours purification et exige qu’on prenne les précautions le mois suivant à la même date.