Sahih al-Bukhari 3263
صحيح البخاري#3263SahihNarrated Aisha:The Prophet (ﷺ) said, "Fever is from the heat of the (Hell) Fire, so cool it with water
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: 59:73