Sahih Muslim | Book 26 | Hadith Number 5485

Narrated by Rafi' b. Khadij
Rafi' b. Khadij reported: I heard Allah's Messenger (may peace be upon him) as saying: The fever is due to the intense heat of Hell, so cool it down in your (bodies) with water. Aba Bakr has made no mention of the word "from you" ('ankum), but he said that Rafi' b. Khadij had informed him of it.