Sahih al-Bukhari 3879
صحيح البخاري#3879SahihNarrated Jabir bin `Abdullah:The Prophet (ﷺ) offered the funeral prayer for Ashama, the Negus, with four Takbir
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: 63:104