Sahih al-Bukhari Book 9, Hadith 17
Allah's Messenger (ﷺ) came out as the sun declined at midday and offered the Zuhr prayer. He then stood on
the pulpit and spoke about the Hour (Day of Judgment) and said that in it there would be tremendous
things. He then said, "Whoever likes to ask me about anything he can do so and I shall reply as long as
I am at this place of mine. Most of the people wept and the Prophet (ﷺ) said repeatedly, "Ask me."
`Abdullah bin Hudhafa As-Sahmi stood up and said, "Who is my father?" The Prophet (ﷺ) said, "Your
father is Hudhafa." The Prophet (ﷺ) repeatedly said, "Ask me." Then `Umar knelt before him and said,
"We are pleased with Allah as our Lord, Islam as our religion, and Muhammad as our Prophet." The
Prophet then became quiet and said, "Paradise and Hell-fire were displayed in front of me on this wall
just now and I have never seen a better thing (than the former) and a worse thing (than the latter).
We were with the Prophet (ﷺ) on a journey and the Mu'adh-dhin (call maker for the prayer) wanted to pronounce the Adhan (call) for the Zuhr prayer. The Prophet (ﷺ) said, 'Let it become cooler." He again (after a while) wanted to pronounce the Adhan but the Prophet (ﷺ) said to him, "Let it become cooler till we see the shadows of hillocks." The Prophet (ﷺ) added, "The severity of heat is from the raging of the Hell-fire, and in very hot weather pray (Zuhr) when it becomes cooler."
Abu Barza said, "The Prophet (ﷺ) used to offer the Fajr (prayer) when one could recognize the person sitting by him (after the prayer) and he used to recite between 60 to 100 Ayat (verses) of the Qur'an. He used to offer the Zuhr prayer as soon as the sun declined (at noon) and the `Asr at a time when a man might go and return from the farthest place in Medina and find the sun still hot. (The sub-narrator forgot what was said about the Maghrib). He did not mind delaying the `Isha prayer to one third of the night or the middle of the night."