The Book of Prayers (Kitab Al-Salat)

Muslim :: Book 4 : Hadith 1288

Hammam b. Munabbih reported: This is what Abu Huraira narrated to us from the Holy Prophet and he transmitted some ahadith-one of them was that the Messenger of Allah (may peace be upon him) said: Let the heat become less severe before prayer, for the intensity of heat is from the exhalation of Hell.