The second ruling: whatever lies outside the hide, such as wool and hair, is pure, while the hide stands between the two; hence it has been given an intermediate ruling.

Through this we come to know the sublimity of the Shariah: it cannot differentiate between two identical things, nor bring together two different things under the same ruling. The purity of hide after tanning is a matter of profound wisdom, as is its impurity upon death, for it is neither like hair, wool, and feathers nor like fat, flesh, and intestines.

Its use after tanning is permissible with dry substances …

His statement, “Its use after tanning is permissible with dry substances,” means that using the hide of carrion after tanning with dry substances is permissible.

The author thereby informs us that using it before tanning is not permissible, whether with dry substances or otherwise, because it is impure.

The apparent meaning of his words is that its use is impermissible even after the hide has dried and become dry. But this is open to question, for we say: if it is dry and used with something dry, the impurity does not transfer. For example, if we cut it into strips and make it into ropes that are not used in direct contact with wet things, there is no objection to this.

His statement, “with dry substances,” excludes wet substances; thus, it may not be used with them—for example, by placing water, milk, or any other wet substance in it—even after tanning. This is because, if it is impure and something wet comes into contact with it, that thing becomes impure through it. But if it is used with something dry and the hide itself is dry, the other thing does not become impure through it, because the ruling of impurity extends only when its trace is transferred. If its trace is not transferred, its ruling does not extend. However, according to the preponderant view—that tanning renders it pure—it may be used with both wet and dry substances.