2. The khuffs—or anything that takes their place—must be lawful footwear. If they are usurped property, or if they are made of silk in the case of a man, wiping over them is not permitted, for no concession can rest on something that is itself forbidden.

3. The khuffs and the like must cover the foot. Hence, wiping is invalid if the footwear does not reach and cover what must ordinarily be washed—for example, if it sits below the ankle—or if it does reach the ankle yet fails to conceal the foot because it is transparent or too thin, such as a flimsy sock. None of these may be wiped over because they do not provide proper coverage.

One may, however, wipe over anything that serves the same purpose as khuffs. It is therefore permissible to wipe over a thick sock that covers the foot, whether of wool or another material, because the Prophet ﷺ wiped over his socks and sandals, as related by Ahmad and others and deemed authentic by al-Tirmidhi. The wiping remains valid for the full prescribed period, regardless of any khuff, sandal, or similar footwear worn over it afterward; repeatedly removing and putting on that outer layer has no effect so long as the wiping began on the sock itself.

It is likewise permissible to wipe over a turban provided two conditions are met:

• First, it must cover the parts of the head that customarily remain concealed.

• Second, the turban must be muḥannak—meaning that at least one turn of it passes under the chin—or it must have a dhuʾābah, namely, a tail that is allowed to hang down from