the term 'habit' is not applied except to that which is frequent, and its minimum is three. Furthermore, most of what is considered by way of repetition is considered as three, such as the days of the option in the 'musarrat' (animal whose milk has been withheld).

Section: The habit is established by discernment. Thus, if she sees dark blood for five days in three months—or two months, according to the other narration—then it becomes red and is continuous, then in the remaining months it becomes ambiguous blood, her habit is the time of the dark blood.

Section: Habits are of two types: consistent and inconsistent. The consistent is that the days are equal, such as four in every month; if she experiences irregular bleeding, she sits for the four days only. As for the inconsistent, if it is in an order—for instance, if she sees three [days] in one month, four in the second, and five in the third, then returns to three, then to four as it was—then if she experiences irregular bleeding in a month and recognizes her turn, she acts accordingly, then according to the one after it, then the one after that, then (12) according to the habit. But if she forgets her turn, we make her sit for the certainty, which is three days; then she performs ghusl and prays for the remainder of the month. If she is certain that it is not the first, but doubts whether it is the second or the third, she sits for four days, because that is the certainty. Then she sits for three days in each of the two other months, then sits for four in the fourth, then returns to three in such a manner forever. One ghusl suffices for her upon the completion of the period she sat for, like the woman who has forgotten, if she sat for the minimum of menstruation; because what is in excess of the certainty is doubtful, so we do not make ghusl mandatory for her based on doubt. It is also possible that ghusl is incumbent upon her upon the passing of her maximum habit, because the certainty of menstruation is established, while the attainment of purity through ghusl is doubtful, and we do not depart from certainty due to doubt. Furthermore, this woman is certain of the obligation of ghusl upon her on one of the three days—on the fifth day—and it has become confused for her, while the validity of her prayer depends on the ghusl; therefore, it is mandatory for her in order to clear her liability with certainty, like one who forgot a prayer from a day but does not know its specific time. This view is more correct for what we have mentioned, and it differs from the woman who has forgotten, for she does not know of any menstruation for herself in excess of what she sat for, whereas this woman is certain of menstruation for herself in excess of what she sat for, and the validity of her prayer depends on her ghusl from it, so that is mandatory. Consequently, according to this, a second ghusl is required of her,