And according to the other report from him, its purity is doubtful, as in Abū Hanīfah’s view: one performs ablution with it and also performs dry ablution.

A third report holds that it is impure because it comes from within an impure animal, and is therefore impure like a dog’s saliva.

However, the Prophet, may Allah bless him and grant him peace, said concerning the cat:

“It is one of those—male and female—who move about among you.”

He thus explained the purity of the water left after a cat drinks by its being among those who move about among us. This indicates that need warrants a ruling of purity. This is part of the argument advanced by those who permit using water left after a mule or donkey has drunk from it, since there is a need for this. Those who prohibit it argue that it is like water left after a dog has drunk: although keeping a dog is permitted for purposes for which it is needed, using the water left after it drinks is prohibited.

Those who allow it respond:

The Prophet permitted keeping a dog because of need, and for this reason forbade taking a price for it. Mules and donkeys are different: selling them is permissible by the agreement of the Muslims. This question rests on the ruling concerning water left after predatory beasts and animals whose meat may not be eaten have drunk from it.

He was asked:

What is the ruling when clay mixed with donkey dung is used to plaster a roof, then rain falls on it and carries some of that mixture with it?

He replied:

Praise be to Allah. If the amount is small, it is excused according to one of the two scholarly views.