Removing impurity from one’s clothes, body, or the prayer-place is a condition for the validity of the prayer; if the impurity remains and one is able to remove it, the prayer is not valid. The proof is the Prophet’s command—peace and blessings be upon him—to wash menstrual blood before performing the prayer.

One must first scrape off the dried blood so that its substance is gone, then rub the spot with water, and finally wash it so that the remaining impurity is removed. This sequence is the optimal way to cleanse a dried impurity: were the order reversed, the impurity would spread and contaminate areas that had previously been clean.

It is permissible for a woman to pray in the garment she was wearing during menstruation; once the soiled area has been scraped and followed up with water, the garment becomes pure. As for the woman’s body, her perspiration, and similar matters, they are pure: she was only instructed to wash the parts of the garment stained with menstrual blood, and everything else retains its original state of purity.

The phrase “then she should pray in it” shows that a dried impurity is not removed—and the place is not purified—except by these three actions; if she omits them, her garment remains impure and her prayer invalid. With regard to blood—and the pus or matter that develops from it—emerging from the rest of the body, the majority of scholars (and it is reported as a consensus) hold it to be impure, though a small amount is excused. Menstrual blood and istiḥāḍa (non-menstrual bleeding), however, are exceptions; no amount of either is overlooked.

The ḥadith proves that the only obligation is to remove the impurity; no specific number of washings is required. If the impurity disappears with a single wash, the place is pure. This is the preponderant view among the scholars, and, God willing, the differing opinions will be detailed later.

Some scholars—including our own—have inferred from the ḥadith that water is indispensable for washing impurities; scraping, rubbing, sunlight, wind, and the like are insufficient. They maintain that water alone is specified for removing impurity, even when the impurity is stubborn.