Hadith 14:257
Abu Bakr narrated to us, he said: Ibn Mahdi narrated to us, from Sufyan, from his father, from 'Abayah ibn Rifa'ah, he said: Rafi' ibn Khadij informed me that the Messenger of Allah (may Allah bless him and grant him peace) said: "Fever is from the heat of Hell, so cool it with water."
حدثنا أبو بكر قال حدثنا بن مهدي عن سفيان عن أبيه عن عباية بن رفاعة قال أخبرني رافع بن خديج أن رسول الله صلى الله عليه وسلم قال الحمى من فور جهنم فأبردوها بالماء