Sahih al-Bukhari 4499
صحيح البخاري#4499SahihNarrated Anas:The Prophet (ﷺ) said, "The prescribed Law of Allah is the equality in punishment (i.e. Al-Qisas)." (In cases of murders, etc)
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: 65:26