Sahih al-Bukhari 847
صحيح البخاري#847SahihNarrated Anas bin Malik:Once the Prophet (ﷺ) delayed the `Isha' prayer until midnight and then came to us. Having prayed he faced us and said, "The people had prayed and slept but you were in the prayer as long as you were waiting for it
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: 10:239