The Mu'adhdbin (the announcer of the hour of prayer) of the Messenger of Allah ﷺ called for the noon prayer. Upon this the Messenger of Allah ﷺ said: Let it cool down, let it cool down, or he said: Wait, wait for the intensity of heat is from the exhalation of Hell. When the heat is intense, delay the prayer till it becomes cooler. Abu Dharr said: (We waited) till we saw the shadow of the mounds.  

أَذَّنَ مُؤَذِّنُ رَسُولِ اللَّهِ ﷺ بِالظُّهْرِ فَقَالَ النَّبِيُّ ﷺ أَبْرِدْ أَبْرِدْ أَوْ قَالَ انْتَظِرِ انْتَظِرْ وَقَالَ إِنَّ شِدَّةَ الْحَرِّ مِنْ فَيْحِ جَهَنَّمَ فَإِذَا اشْتَدَّ الْحَرُّ فَأَبْرِدُوا عَنِ الصَّلاَةِ قَالَ أَبُو ذَرٍّ حَتَّى رَأَيْنَا فَىْءَ التُّلُولِ  

Yahya related to me from Malik from Abu'z Zinad from al-Araj from Abu Hurayra that the Messenger of Allah ﷺ said, "When the heat is fierce, wait until it gets cooler before you do the prayer, for scorching heat is from the blast of Jahannam."  

أَنَّ رَسُولَ اللَّهِ ﷺ قَالَ إِذَا اشْتَدَّ الْحَرُّ فَأَبْرِدُوا عَنِ الصَّلاَةِ فَإِنَّ شِدَّةَ الْحَرِّ مِنْ فَيْحِ جَهَنَّمَ  

The Mu'adh-dhin (call-maker) of the Prophet ﷺ pronounced the Adhan (call) for the Zuhr prayer but the Prophet said, "Let it be cooler, let it be cooler." Or said, 'Wait, wait, because the severity of heat is from the raging of the Hell-fire. In severe hot weather, pray when it becomes (a bit) cooler and the shadows of hillocks appear." (Using translation from Bukhārī 535)  

أَذَّنَ مُؤَذِّنُ رَسُولِ اللهِ ﷺ بِالظُّهْرِ فَقَالَ النَّبِيُّ ﷺ أَبْرِدْ أَبْرِدْ أَوْقَالَ انْتَظِرْ انْتَظِرْ وَقَالَ إِنَّ شِدَّةَ الْحَرِّ مِنْ فَيْحِ جَهَنَّمَ فَإِذَا اشْتَدَّ الْحَرُّ فَأَبْرِدُوا عَنِ الصَّلَاةِ قَالَ أَبُو ذَرٍّ حَتَّى رَأَيْنَا فَيْءَ التُّلُولِ  

[Machine] "We came from a funeral, and we passed by Abu Dharr. He said, 'We were with the Prophet ﷺ on a journey when the Muadhin (caller to prayer) wanted to call the Adhan for Dhuhr prayer. The Prophet ﷺ said, 'Cool down (wait), then he wanted to call the Adhan again, and the Prophet ﷺ said, 'Cool down,' and on the third time he said, 'The third time is the most knowledgeable. Then we saw the shade of a tree and the Prophet ﷺ said, 'Indeed, the intensity of the heat is from the heat of Hellfire, so when the heat intensifies, cool down with prayer.'"  

جِئْنَا مِنْ جَنَازَةٍ فَمَرَرْنَا بِأَبِي ذَرٍّ فَقَالَ كُنَّا مَعَ رَسُولِ اللهِ ﷺ فِي سَفَرٍ فَأَرَادَ الْمُؤَذِّنُ أَنْ يُؤَذِّنَ لِلظُّهْرِ فَقَالَ رَسُولُ اللهِ ﷺ أَبْرِدْ ثُمَّ أَرَادَ أَنْ يُؤَذِّنَ فَقَالَ لَهُ أَبْرِدْ وَالثَّالِثَةَ أَكْبَرُ عِلْمِي شُعْبَةُ قَالَ لَهُ حَتَّى رَأَيْنَا فَيْءَ التُّلُولِ قَالَ إِنَّ شِدَّةَ الْحَرِّ مِنْ فَيْحِ جَهَنَّمَ فَإِذَا اشْتَدَّ الْحَرُّ فَأَبْرِدُوا بِالصَّلَاةِ  

[Machine] We were informed by a migrant, Abi al-Hasan from the tribe of Taym Allah, who was their freed slave. He said, "We returned from a funeral procession and passed by Zaid ibn Wahb, who narrated from Abu Dharr. He said, 'We were traveling with the Prophet ﷺ when the Mu'adhin wanted to call the adhan. The Prophet ﷺ told him to wait and then he wanted to call the adhan again. The Prophet ﷺ told him to wait, and he repeated this three times. Until we saw the shade of the black crow. The Prophet ﷺ prayed and then said, 'The intensity of the heat is from the breath of Hell. So, when the weather is hot, cool yourselves with prayer.'"  

أَخْبَرَنَا عَنْ مُهَاجِرٍ أَبِي الْحَسَنِ مِنْ بَنِي تَيْمِ اللهِ مَوْلًى لَهُمْ قَالَ رَجَعْنَا مِنْ جَنَازَةٍ فَمَرَرْنَا بِزَيْدِ بْنِ وَهْبٍ فَحَدَّثَ عَنْ أَبِي ذَرٍّ قَالَ كُنَّا مَعَ النَّبِيِّ ﷺ فِي سَفَرٍ فَأَرَادَ الْمُؤَذِّنُ أَنْ يُؤَذِّنَ فَقَالَ النَّبِيُّ ﷺ أَبْرِدْ ثُمَّ أَرَادَ أَنْ يُؤَذِّنَ فَقَالَ النَّبِيُّ ﷺ أَبْرِدْ قَالَهَا ثَلَاثَ مَرَّاتٍ قَالَ حَتَّى رَأَيْنَا فَيْءَ التُّلُولِ فَصَلَّى ثُمَّ قَالَ إِنَّ شِدَّةَ الْحَرِّ مِنْ فَيْحِ جَهَنَّمَ فَإِذَا اشْتَدَّ الْحَرُّ فَأَبْرِدُوا بِالصَّلَاةِ  

[Machine] Abu Dharr heard the Messenger of Allah ﷺ saying: "We were with the Messenger of Allah ﷺ during a journey and the Muadhin intended to call the Adhan for Dhur prayer. The Prophet ﷺ told him, 'Cool down.' Then he intended to call the Adhan again and the Prophet ﷺ told him, 'Cool down' two or three times until we saw the shadow of a hillock. The Prophet ﷺ then said, 'Indeed, the intense heat is a portion of the Hellfire. So when it is extremely hot, cool yourselves with prayer.'"  

سَمِعَ أَبَا ذَرٍّ يَقُولُ كُنَّا مَعَ رَسُولِ اللَّهِ ﷺ فِي سَفَرٍ فَأَرَادَ الْمُؤَذِّنُ أَنْ يُؤَذِّنَ بِالظُّهْرِ فَقَالَ لَهُ النَّبِيُّ ﷺ «أَبْرِدْ» ثُمَّ أَرَادَ أَنْ يُؤَذِّنَ فَقَالَ لَهُ «أَبْرِدْ» مَرَّتَيْنِ أَوْ ثَلَاثًا حَتَّى رَأَيْنَا فَيْءَ التُّلُولِ وَقَالَ «إِنَّ شِدَّةَ الْحَرِّ مِنْ فَيْحِ جَهَنَّمَ فَإِذَا اشْتَدَّ الْحَرُّ فَأَبْرِدُوا بِالصَّلَاةِ»