Sayyiduna Anas (may Allah be pleased with him) narrates: A man used to clean the (Prophet’s) Mosque. He passed away and was buried at night. When the Prophet (peace and blessings be upon him) was informed about this, he said:“Take me to his grave!”Then the Prophet (peace and blessings be upon him) and others with him went to that man’s grave. The Prophet (peace and blessings be upon him) said:“These graves are full of darkness for their inhabitants (i.e., the dead), and Allah, because of my prayer over them, illuminates their graves for them.”Then the Prophet (peace and blessings be upon him) came to that man’s grave and performed his funeral prayer. These are the words of the narration from the narrator named Ali bin Muslim.