Sunan an-Nasa'i 5436
It was narrated that 'Uqbah bin 'Amir said:
"I was leading the Messenger of Allah [SAW] (on his mount) on a journey, and the Messenger of Allah [SAW] said: 'O 'Uqbah, shall I not teach you the best two Surahs that can be recited?' And he taught me: 'Say: I seek refuge with (Allah) the Lord of the daybreak.' And 'Say: I seek refuge with (Allah) the Lord of mankind...' He thought that I did not seem too overjoyed with them, so when he stopped to pray Subh, he recited them when he led the people in the Subh prayer. When the Messenger of Allah [SAW] finished praying, he turned to me and said: 'O 'Uqbah, what do you think?'"
أَخْبَرَنَا أَحْمَدُ بْنُ عَمْرٍو، قَالَ أَنْبَأَنَا ابْنُ وَهْبٍ، قَالَ أَخْبَرَنِي مُعَاوِيَةُ بْنُ صَالِحٍ، عَنِ ابْنِ الْحَارِثِ، - وَهُوَ الْعَلاَءُ - عَنِ الْقَاسِمِ، مَوْلَى مُعَاوِيَةَ عَنْ عُقْبَةَ بْنِ عَامِرٍ، قَالَ كُنْتُ أَقُودُ بِرَسُولِ اللَّهِ صلى الله عليه وسلم فِي السَّفَرِ فَقَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم ‏"‏ يَا عُقْبَةُ أَلاَ أُعَلِّمُكَ خَيْرَ سُورَتَيْنِ قُرِئَتَا ‏"‏ ‏.‏ فَعَلَّمَنِي ‏{‏ قُلْ أَعُوذُ بِرَبِّ الْفَلَقِ ‏}‏ وَ ‏{‏ قُلْ أَعُوذُ بِرَبِّ النَّاسِ ‏}‏ فَلَمْ يَرَنِي سُرِرْتُ بِهِمَا جِدًّا فَلَمَّا نَزَلَ لِصَلاَةِ الصُّبْحِ صَلَّى بِهِمَا صَلاَةَ الصُّبْحِ لِلنَّاسِ فَلَمَّا فَرَغَ رَسُولُ اللَّهِ صلى الله عليه وسلم مِنَ الصَّلاَةِ الْتَفَتَ إِلَىَّ فَقَالَ ‏"‏ يَا عُقْبَةُ كَيْفَ رَأَيْتَ ‏"‏ ‏.‏