Sahih al-Bukhari 458
صحيح البخاري#458SahihNarrated Abu Huraira:A black man or a black woman used to sweep the mosque and he or she died. The Prophet (ﷺ) asked about her (or him). He was told that she (or he) had died. He said, "Why did you not inform me? Show me his grave (or her grave)." So he went to her (his) grave and offered her (his) funeral prayer
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Every narration in Sahih al-Bukhari is accepted as Sahih (authentic) by the established status of the book.
In-book reference: 8:106