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485. Women who have the habit of time and duration are of two types:
1. A woman who observes the blood of Îayà at a particular time (of the month) in two consecutive months, and is purified from it at a particular time as well. An example would be a woman who observes the blood of Îayà on the first day of the month and is purified from it on the seventh day, in two consecutive months, whereby causing her habit of Îayà to be from the first of the month to the seventh.
2. A woman who observes the blood of Îayà at a particular time in two consecutive months, and after observing blood for three or more days, she is purified from it for one or more days, and then observes blood once again, given the following two conditions:
1. The sum of the days she observes blood and the days that she is purified from it, does not exceed ten days
2. The sum of the days she observes blood and the days she is purified from it, is the same in both months
In this case her habitual duration will be the length of the days she observed blood and the days that she was purified from it. It is also not necessary for the interval of purity to be of the same duration in both months. An example of this would be a woman who observes blood from the first of the month to the third in the first month, and is then purified from it, and thereafter observes blood once again for three days. In the second month, she observes blood for three days, and is then purified from it for less than three days or more than it, and thereafter observes blood once again, and their sum equals nine days. In this case she will be a ÎÁÞià for all the nine days, and her habitual duration will be nine days as well.

486. If a woman with the habit of time and duration observes blood at her habitual time, or a little before it—albeit to an extent that the common understanding would consider her menses to be early—she must act upon the rulings of a ÎÁÞià that were mentioned earlier, even if the blood does not possess the qualities of ÎayÃ. If she later comes to realize that it was not Îay×for example, if she is purified from it prior to completing three days—she should offer the qaÃÁ of all the rituals of worship that she had not performed.
The same will apply if it is delayed from the first day of her habit, but does not occur outside her habitual days.
As for the blood that she observes outside her habitual days, and does not possess the qualities of ÎayÃ, it will not be considered Îayà if it occurs two or more days after the end of her habitual days. If it occurs less than two days after her habitual days, obligatory precaution dictates that she combine the prohibitions of a ÎÁÞià and the obligations of a mustaÎÁÃah.

487. If a woman with the habit of time and duration observes blood for the entire duration of her habitual days, and a few days before it—albeit to an extent that the common understanding would consider her menses to be early or with the qualities of Îayà —and after it with the qualities of ÎayÃ, and the sum of the days does not exceed ten, all of the blood will be ÎayÃ. If it exceeds ten days, then only the blood observed during her habitual days will be ÎayÃ, and the blood observed before it and after it is istiÎÁÃah. She must also offer the qaÃÁ of the rituals of worship that she did not perform during the days preceding her habitual days, and the days after it.
If she observes blood during her habitual days, and a few days before it— albeit to an extent that the common understanding would consider her menses to be early or with the qualities of Îayà —and the sum of the days does not exceed ten, then all of it is ÎayÃ. If it exceeds ten days, it is Îayà only during her habitual days, and the blood observed prior to it will be istiÎÁÃah. If she had not performed her rituals of worship during those days, she should offer their qaÃÁ.
If she observes blood during her habitual days, and a few days after it with the qualities of ÎayÃ, and the sum of the days does not exceed ten, then all of it is ÎayÃ. If the blood does not possess the qualities of Îayà during the days following her habitual days, obligatory precaution dictates that she combine the prohibitions of a ÎÁÞià and the obligations of a mustaÎÁÃah during those days. If the sum of the days exceeds ten, it will be Îayà during her habitual days and istiÎÁÃah during the rest.

488. If a woman with the habit of time and duration observes blood during a part of her habitual days, along with a few days prior to it—albeit to an extent that the common understanding would consider her menses to be early, or if it possesses the qualities of Îay×and the sum of the days does not exceed ten, then all of it is ÎayÃ. If it exceeds ten days, then it is Îayà for the days she observed blood during her habitual days, in addition to a few days prior to it—albeit to an extent that the common understanding would consider her menses to be early, or if it possesses the qualities of Îay×for as long as the sum of the days is equivalent to her habitual days. In the days preceding it, it will be istiÎÁÃah.
If she observes blood during a part of her habitual days, along with a few days after it, and the sum of the days does not exceed ten, all of it will be ÎayÃ, provided the blood observed after the habitual days possesses the qualities of ÎayÃ. If it does not possess the qualities of ÎayÃ, she should consider it to be Îayà for the length of (the days she observed blood during) her habitual days and the days following it for as long as their sum is equivalent to her habitual days. From the days that exceed this sum until the tenth day, obligatory precaution dictates that she combine the prohibitions of a ÎÁÞià and the obligations of a mustaÎÁÃah. If it exceeds ten days, she should consider it as Îayà for the length of her habitual days, and istiÎÁÃah for the rest.

489. If a woman with a habit (in her menses) observes blood for three days or more, and is then purified from it, and then observes blood once again, and the days between the two discharges is less than ten, whilst the sum of all the days that she observed blood and the days that she was purified is more than ten—for example, after observing blood for five days, she is purified for five days, and observes blood once again for another five days—then such a case can take on the following forms:
a. All the blood that was observed during the first discharge occurs during her habitual days, and the second discharge, which was observed after she was purified, does not occur during her habitual days, in which case she must consider all of the first discharge as Îayà and the second discharge as istiÎÁÃah. The same will apply if she observes a part of the discharge during her habitual days and a part of it before it—albeit to an extent that the common understanding would consider her menses to be early—or if it possesses the qualities of ÎayÃ, be it before her habitual days or after it.
b. The first discharge does not occur during her habitual days, whilst the entire second discharge or a part of it, as elaborated in the previous case, occurs during her habitual days, in which case she must consider all of the second discharge as Îayà and all of the first as istiÎÁÃah.
c. A portion of the first and second discharge occurs during the habitual days, and the portion of the first discharge that was observed during the habitual days is not less than three days, in which case all the blood will be Îayà as long as the sum of that portion, and the days that she was purified between the two, and the part of the second discharge which occurred during her habitual days does not exceed ten days. The portion of her first discharge which occurred prior to her habitual days, and the portion of the second discharge which occurred after her habitual discharge, will be considered as istiÎÁÃah. For example, if her habitual days were from the third to the tenth of the month, and she observes blood from the first to the sixth in a particular month, after which she is purified from it for two days and then observes blood until the fifteenth, it will be Îayà from the third to the tenth. On the first and the second day, as well as the eleventh to the fifteenth, it will be istiÎÁÃah.
d. A portion of the first and second discharge occurs during the habitual days, however the portion of the first discharge which occurs during her habitual days is less than three days, in which case she must combine the prohibitions of a ÎÁÞià and the obligations of a mustaÎÁÃah during both discharges. During the interval of purity, she should combine the prohibitions of a ÎÁÞià and the obligations of a woman who is pure from bleeding.

490. If a woman with the habit of time and duration does not observe blood during her habitual days, but observes blood during days other than it for the length of her days of ÎayÃ, in the event that it possesses the qualities of ÎayÃ, she should consider it as ÎayÃ.

491. If a woman with the habit of time and duration observes blood at her habitual time, and it is not for less than three days, however its duration is more or less than her (usual) habit, and then she is purified from bleeding, only to observe blood once again for the duration of her habitual days, possessing the qualities of ÎayÃ, she should consider all of it as Îayà as long as the sum of the days of both discharges and the interval of purity in between does not exceed ten days. If it does exceed ten days, she should consider the blood observed during her habitual days as Îayà and the other blood as istiÎÁÃah.

492. If a woman with the habit of time and duration observes blood for more than ten days, the blood that she observed in her habitual days will be ÎayÃ, even if it does not possesses the qualities of ÎayÃ. The blood observed after her habitual days will be istiÎÁÃah, even if it possesses the qualities of ÎayÃ. For example, if a woman whose habit of Îayà is from the first to the seventh of the month, observes blood from the first of the month to the twelfth, during the first seven days it will be Îayà and during the following five days it will be istiÎÁÃah.