Jabir b. 'Abd Allah said: A man declared that his slave would be free after his death, but he had no other property. So the Prophet (ﷺ) ordered (to sell him). He was then sold for seven hundred or nine hundred (dirhams)
SahihSahihSahih Bukhari (2230) Sahih Muslim (997 After 1668)Book 31 · Hadith 30