It is narrated from Sayyiduna Abu Hurairah, may Allah be pleased with him, that a slave woman or a man used to clean the mosque. When the Prophet Muhammad, peace and blessings be upon him, did not find him, he inquired about him. They said: He has passed away. The Prophet, peace and blessings be upon him, said: "Why did you not inform me about him?" They replied, and the Prophet, peace and blessings be upon him, said: "Show me his grave." So the Prophet, peace and blessings be upon him, came to his grave and offered his funeral prayer.