Volume 4, Book 54, Number 480:
Narrated Abu Dhar:
While the Prophet was on a journey, he said (regarding the performance of the Zuhr prayer),
“Wait till it (i.e. the weather) gets cooler.” He said the same again till the shade of the hillocks exten –
ded. Then he said, “Delay the (Zuhr) Prayer till it gets cooler, for the severity of heat is from the in –
crease in heat of Hell (fire).”