whether in a mosque or elsewhere. This is a point of disagreement among the scholars, based on the Prophet’s statement, “It is forbidden.” Does the pronoun refer to the uses mentioned by the Companions, or to the sale which the Messenger of Allah (peace and blessings be upon him) mentioned?

The latter is one view, while the former is another. And Allah knows best.

Excluded from the category of carcasses is every carcass that is lawful to eat.

Also excluded from the parts of a carcass are:

First: those parts regarded as legally detached, such as hair, camel hair, wool, feathers, and the like. These may be sold, because they are pure. Thus, if a person’s sheep dies while it has wool on it, and he shears and sells the wool, there is nothing wrong with that.

Second: according to the stronger view, the skin is also excluded, because it can be purified; it is therefore like a garment contaminated by impurity.

It was also said that it is not excluded, because it is one of the carcass’s parts and is therefore impure. Moreover, we do not know whether the person who buys it will tan it and thereby purify it or not. This view is more cautious, but the first is more firmly based: so long as it can be purified and put to use, it may be sold. The school’s position is that the skin of a carcass is not purified by tanning and may not be sold—even after tanning—because it may be used only for dry items.

And that it be sold by its owner or someone acting in his stead …

The author’s statement, “And that it be sold by its owner”: this is the fourth condition for the validity of a sale—that it be made by the owner or by someone acting in his stead.

The evidence for this condition is found in the Quran, the sunnah, and sound reasoning.

As for the Quran, Allah, exalted is He, says: “O you who believe, do not consume one another’s wealth unjustly, unless it be through trade by mutual consent”