Mishkat al-Masabih, hadith 591

وَعَنْ زَيْدِ بْنِ ثَابِتٍ قَالَ: كَانَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يُصَلِّي الظُّهْرَ بِالْهَاجِرَةِ وَلَمْ يَكُنْ يُصَلِّي صَلَاةً أَشَدَّ عَلَى أَصْحَابِ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مِنْهَا فَنَزَلَتْ (حَافِظُوا عَلَى الصَّلَوَاتِ وَالصَّلَاةِ الْوُسْطَى) وَقَالَ إِنَّ قَبْلَهَا صَلَاتَيْنِ وَبَعْدَهَا صَلَاتَيْنِ. رَوَاهُ أَحْمد وَأَبُو دَاوُد

Zaib b. Thabit said that God’s Messenger used to pray the noon prayer in the extreme heat, observing no prayer more severe to his companions than it. Then was revealed, “And observe carefully the prayers and the middle prayer”; (Al-Qur’an, 2:238) and he said, “Before it there are two times of prayer and after it there are two times of prayer.” Ahmad and Abu Dawud transmitted it.