Sahih al-Bukhari 3994
صحيح البخاري#3994SahihNarrated Mu`adh:The one who asked (the Prophet) was Gabriel (refer to Hadith)
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: 64:45