Sahih al-Bukhari 6760
صحيح البخاري#6760SahihNarrated Aisha:Allah's Messenger (ﷺ) said, "The wala is for the one who gives the silver (pays the price) and does the favor (of manumission after paying the price)
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: 85:37