Sahih al-Bukhari 1552
صحيح البخاري#1552SahihNarrated Ibn `Umar:The Prophet (ﷺ) recited Talbiya when he had mounted his Mount and was ready to set out
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: 25:38