It is Better for an Endowment to be Spent on the Thing For Which it Was Specified
Question:
A man paid some money to the committee of a mosque, and it was said to him that this money would be used for building things such as toilets, but the majority of the committee later considered that they needed to spend the money on something other than that specified by the owner of the money, or that they were in no need. What is the ruling?
Answer:
It is preferable and more prudent that it be spent on the thing specified by the one who gave it, if it was some prescribed thing, such as toilets or something else allowed. However, if the committee established for building the mosque considered that need or necessity called for it being spent on building the mosque, there is no sin in that - Allah Willing - because building a mosque is better, and of greater benefit than building toilets near a mosque. This is only because building a mosque is the primary goal, while building toilets falls under the category of means and support facilitating the performance of prayer, and increasing the number of worshippers. And Allah knows best.
Source:
Shaykh `Abdul-`Azeez Bin Baz
Fatawa Islamiyah, volume 5 / page 46
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