Sayyidina Abu Dharr (RA) said that Allahs Messenger ﷺ was on a journey and Sayyidina Bilal (RA) was with him too. He intended to call the iqamah for the Salah of Zuhr, but the Prophet ﷺ said, "Let It cool down!" Then he again Intended to call..Allahs Messenger ﷺ said, "Let it be cooler for the Zuhr", till they saw the shadows of hillocks and called the iqamah and offered the Salah of Zuhr. Then Allahs Messenger ﷺ said, "The extreme heat is the severity of Hell. So, observe the Salah of Zuhr when it is cooler.”