This excerpt is taken from the book of Fazilat-ul-Sheikh Abdul Salam Rustami From Denial of Hadith to Denial of Quran.
Hadith 32: Fever is caused by the heat (blowing) of Hellfire
The Messenger of Allah, peace be upon him, said:
"Fever is caused by the heat of Hellfire, so cool it with water."
Reference: Sahih al-Bukhari, Beginning of Creation, Chapter on the Description of the Fire and that it is Created, Hadith: 3263, and Hadith Location, p. 334
This hadith actually relates to faith in the unseen, as has been discussed in the context of weather changes. Some scholars interpret this hadith as a metaphor, meaning the heat of fever is like the heat of Hellfire in pain and suffering. However, the correct opinion is that fever is a heat produced in the body when the centers of Allah's creation are affected by germs, and this heat is from Hellfire, meaning Allah Almighty has taken a small portion of the heat from Hellfire and spread it on earth. When the causes of this heat appear in a person, Allah Almighty inflicts this heat upon him. Thus, the hadith explains the original source and basis of the heat. Contemporary doctors also recommend the treatment method mentioned in the hadith, that is, according to them, treating it with water is still an effective method. Pouring cold water or applying ice packs reduces the temperature and the fever subsides quickly. If one reflects here, this treatment was revealed to the Prophet Muhammad, peace be upon him, through divine revelation, while doctors accept it after many experiments. Therefore, this is a great proof of the truthfulness of prophethood and the authenticity of the hadith.
