Building a Room or Chamber in the Mosque; Resting a Beam or Girder on the Mosque Wall
Question
The courtyard of a Congregational Mosque, where prayer has been performed for a long time and on which the lines of the rows are regularly marked — may a chamber be built in some part of this courtyard or not? Or may shops be built or not?
Answer
If a place is dedicated as waqf for prayer and adhan and congregation begin to be held there — that is, it becomes a mosque in the Sharʿi sense — then it is not permissible to put it permanently to any other use. Therefore neither a chamber nor a shop may be built there: [ar]شَرْطُ الْوَاقِفِ كَنَصِّ الشَّارِعِ[/ar] “The condition of the waqif is like the text of the Lawgiver.
Source: Fatawa Mahmudiyya
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