in stagnant water, nor should he bathe in it to remove major ritual impurity.”

He—peace and blessings be upon him—also said, “When any one of you wakes up from sleep, let him not immerse his hand in the vessel until he has washed it three times, for he does not know where his hand spent the night.”

As for running water: if some impurity should fall into it, performing wudu from it remains permissible so long as no trace of the impurity is visible, because the flow of the water prevents the impurity from settling. Likewise, in the case of a large pool whose far side is not disturbed when the near side is moved, if the impurity falls at one edge it is permissible to take wudu from the opposite edge, for it is presumed that the impurity does not reach that side.

The death, in the water, of any creature that has no flowing blood—such as bedbugs, flies, wasps, or scorpions—does not render the water impure. Nor does the death, within the water, of creatures that ordinarily live in it—like fish, frogs, or crabs—spoil the water.

Used water may not be employed for lifting ritual impurity. “Used water” is any water by which impurity was removed or that was applied to the body as an act of worship.

Every hide that has been tanned is deemed pure; one may pray wearing it and use water kept in it for wudu, except in the case of swine hide and human skin.

The hair of a dead animal and its bones are likewise pure.