A dry adherent mass can separate from the surface of leather through rubbing, whereas filth penetrating textile fibres generally cannot be presumed removed by rubbing alone.
The khuff ruling thus relies on removal of the actual impurity and is not a general permission to avoid washing soiled fabrics.
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Types of Impurity and Methods of Purification
A dry adherent mass can separate from the surface of leather through rubbing, whereas filth penetrating textile fibres generally cannot be presumed removed by rubbing alone.
The khuff ruling thus relies on removal of the actual impurity and is not a general permission to avoid washing soiled fabrics.