The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 2130

Abu Huraira reported: The Apostle of Allah (may peace be upon him) visited the grave of his mother and he wept, and moved others around him to tears, and said: I sought permission from my Lord to beg forgiveness for her but it was not granted to me, and I sought permission to visit her grave and it was granted to motel So visit the graves, for that makes you mindful of death.

Source materials are from the University of Southern California MSA site
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