Is it permissible to construct mosques upon graves?
General Chapter
Al-Mughni
Book of Funerals
Primary text
It is prohibited to construct mosques upon graves based on the Prophetic tradition where the Prophet, peace be upon him, cursed the Jews for taking the graves of their prophets as places of prayer, as a warning against similar actions, as narrated in the Muttafaq 'alayh collection. Aisha, may Allah be pleased with her, stated that the grave of the Messenger of Allah, peace be upon him, was not made prominent lest it be taken as a mosque.
Supporting text
Singling out graves for prayer near them resembles the veneration of idols through prostration to them and drawing near to them. It has been transmitted that the beginning of idol worship was the glorification of the deceased through making their images, wiping them, and praying near them.