The transaction of something that has been given as a charitable endowment (waqf) is invalid. However, if the thing is damaged to the extent that it can no longer be used for the purpose for which it was endowed, or it is close to reaching this stage – for example, the ḥaṣīr[1] of a mosque is so torn that one cannot perform prayers on it – then there is no problem if the trustee (mutawallī) or someone who is ruled to be in his position sells it. But wherever possible, the money acquired should – based on recommended precaution – be used in the same mosque in a manner that is most congruous with the aims of the endower (wāqif).