Sahih al-Bukhari 5604
صحيح البخاري#5604SahihNarrated Um Al-Fadl:The people doubted whether Allah's Messenger (ﷺ) was fasting or the Day of `Arafat or not. So I sent a cup containing milk to him and he drank 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: 74:30