Sahih al-Bukhari 5723
Sahih al-Bukhari · Book 76: Medicine · Fever is from the heat of Hell
Narrated Nazi':
حَدَّثَنِي يَحْيَى بْنُ سُلَيْمَانَ ، حَدَّثَنِي ابْنُ وَهْبٍ ، قَالَ حَدَّثَنِي مَالِكٌ ، عَنْ نَافِعٍ ، عَنِ ابْنِ عُمَرَ ـ رضى الله عنهما ـ عَنِ النَّبِيِّ صلى الله عليه وسلم قَالَ " الْحُمَّى مِنْ فَيْحِ جَهَنَّمَ فَأَطْفِئُوهَا بِالْمَاءِ " . قَالَ نَافِعٌ وَكَانَ عَبْدُ اللَّهِ يَقُولُ اكْشِفْ عَنَّا الرِّجْزَ .
`Abdullah bin `Umar said, "The Prophet (ﷺ) said, 'Fever is from the heat of Hell, so put it out (cool it) with water.' " Nafi` added: `Abdullah used to say, "O Allah! Relieve us from the punishment," (when he suffered from fever).