Sahih al-Bukhari 7186
صحيح البخاري#7186SahihNarrated Jabir:The Prophet (ﷺ) came to know that one of his companions had given the promise of freeing his slave after his death, but as he had no other property than that slave, the Prophet (ﷺ) sold that slave for 800 dirhams and sent the price to him
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: 93:48