The Messenger of Allah ﷺ said, "Fever comes from the blazing heat of Hell, so cool it down with water."
أن رسول الله ﷺ قال: الحمى من فيح جهنم فأطفئوها بالماء.
Malik reported it in "The Evil Eye" (16), from Nafi, from Ibn Umar, as mentioned. Bukhari reported it in "Medicine" (5723), and Muslim in "Greetings" (2209:79), through the route of Malik, in like manner.His saying "fayh" means the intensity and surging of heat. It is also said with a waw, "fawh." One says, "The pot faaha (fayh/fawh)" when it boils over.