Mukhtasar Bukhari

Narrated Abu Huraira (may Allah be pleased with him) from the Prophet (peace and blessings of Allah be upon him) that he said: "When the heat becomes intense, perform the prayer when it cools down, because the severity of heat is from the raging of Hell. And Hell complained to its Lord and said: O my Lord! One part of me has consumed another part. So Allah allowed it two breaths, one in the winter and one in the summer. And that is the severe heat which you feel and the severe cold which you experience."

Sayyiduna Abu Dharr Ghifari (may Allah be pleased with him) narrates: We were on a journey with the Prophet (peace and blessings of Allah be upon him). The mu’adhdhin wanted to give the adhan for Zuhr, so the Prophet (peace be upon him) said to him: “Let it cool down.” Then he wanted to give the adhan again, and the Prophet (peace be upon him) said to him: “Let it cool down.” This continued until we saw the shade of the hills. Then the Prophet (peace be upon him) said: “The severity of heat is from the boiling of Hell, so when the heat is intense, perform (the Zuhr) prayer when it cools down.”