Musnad Ishaq

Benefits:
From the aforementioned hadith, it is understood that building mosques upon graves is not permissible. Sayyidah Aisha radi Allahu anha narrates that when the Messenger of Allah sallallahu alayhi wa sallam fell ill, some of his noble wives mentioned a church which they had seen in Abyssinia. Both Sayyidah Umm Salamah and Sayyidah Umm Habibah radi Allahu anhuma had gone to the land of Abyssinia. They also mentioned its beauty and the images placed within it. Upon this, the Prophet sallallahu alayhi wa sallam raised his head and said: “When a righteous man among them would die, they would build a mosque over his grave, then place his image in it. These are the worst of Allah’s creation in the sight of Allah.” (Bukhari, no. 1341; Muslim, no. 528)

In another narration, the Prophet sallallahu alayhi wa sallam said: “Indeed, the worst people are those upon whom the Hour will be established and those who take graves as mosques.” (Ahkam al-Jana’iz: p. 278; Sahih Ibn Hibban, no. 340)

Imam San‘ani rahimahullah states: Both meanings are included in taking graves as mosques: (1).... Performing prayer facing the graves. (2).... Performing prayer upon the graves (by building mosques over them). (Subul al-Salam: 1/214)

Allamah Nasir al-Din al-Albani rahimahullah has said that three matters are included in taking graves as mosques: (1).... Performing prayer facing the graves. (2).... Prostrating upon the graves. (3).... Building mosques upon the graves. (Ahkam al-Jana’iz wa Bida‘uha: p. 279)