Building a Mosque on Land That Is Not Waqf
Question
A mosque was being built in a village; only the foundation had been laid when the construction stopped. The fact is that part of it was not owned property (ghayr milk) and is now the property of the village community, right next to which a house has been built, so that only three and three-quarter feet of space remain, which causes inconvenience to the people of the neighbourhood. In short, for the land behind the mosque as well, permission had not been taken from the owner of the land.
Answer
Since the owner did not make that land waqf, and it is not waqf even now, a mosque should not be built there.
Source: Fatawa Mahmudiyya
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