Sahih Bukhari Volume 5, Book 64, Hadith 4179

حَدَّثَنِي عَبْدُ اللَّهِ بْنُ يُوسُفَ، أَخْبَرَنَا مَالِكٌ، عَنْ زَيْدِ بْنِ أَسْلَمَ، عَنْ أَبِيهِ، أَنَّ رَسُولَ اللَّهِ صلى الله عليه وسلم كَانَ يَسِيرُ فِي بَعْضِ أَسْفَارِهِ، وَعُمَرُ بْنُ الْخَطَّابِ يَسِيرُ مَعَهُ لَيْلاً، فَسَأَلَهُ عُمَرُ بْنُ الْخَطَّابِ عَنْ شَىْءٍ فَلَمْ يُجِبْهُ رَسُولُ اللَّهِ صلى الله عليه وسلم ثُمَّ سَأَلَهُ فَلَمْ يُجِبْهُ، ثُمَّ سَأَلَهُ فَلَمْ يُجِبْهُ وَقَالَ عُمَرُ بْنُ الْخَطَّابِ ثَكِلَتْكَ أُمُّكَ يَا عُمَرُ، نَزَرْتَ رَسُولَ اللَّهِ صلى الله عليه وسلم ثَلاَثَ مَرَّاتٍ، كُلُّ ذَلِكَ لاَ يُجِيبُكَ‏.‏ قَالَ عُمَرُ فَحَرَّكْتُ بَعِيرِي ثُمَّ تَقَدَّمْتُ أَمَامَ الْمُسْلِمِينَ، وَخَشِيتُ أَنْ يَنْزِلَ فِيَّ قُرْآنٌ، فَمَا نَشِبْتُ أَنْ سَمِعْتُ صَارِخًا يَصْرُخُ بِي ـ قَالَ ـ فَقُلْتُ لَقَدْ خَشِيتُ أَنْ يَكُونَ نَزَلَ فِيَّ قُرْآنٌ‏.‏ وَجِئْتُ رَسُولَ اللَّهِ صلى الله عليه وسلم فَسَلَّمْتُ عَلَيْهِ فَقَالَ ‏"‏ لَقَدْ أُنْزِلَتْ عَلَىَّ اللَّيْلَةَ سُورَةٌ لَهِيَ أَحَبُّ إِلَىَّ مِمَّا طَلَعَتْ عَلَيْهِ الشَّمْسُ، ثُمَّ قَرَأَ ‏{‏إِنَّا فَتَحْنَا لَكَ فَتْحًا مُبِينًا‏}‏‏.‏‏"‏

Narrated By Zaid bin Aslam : My father said, "Allah's Apostle was proceeding at night on one of his journeys and 'Umar bin Al-Khattab was going along with him. 'Umar bin Al-Khattab asked him (about something) but Allah's Apostle did not answer him. 'Umar asked him again, but he did not answer him. He asked him again (for the third time) but he did not answer him. On that Umar bin Al-Khattab addressed himself saying, "May your mother be bereaved of you, O 'Umar, for you have asked Allah's Apostle thrice, yet he has not answered you." 'Umar said, "Then I made my camel run fast and took it in front of the other Muslims, and I was afraid that something might be revealed in my connection. I had hardly waited for a moment when I heard somebody calling me. I said, 'I was afraid that something might have been revealed about me.' Then I came to Allah's Apostle and greeted him. He (i.e. the Prophet) said, 'Tonight there has been revealed to me, a Sura which is dearer to me than (all the world) on which the sun rises,' and then he recited: 'Verily! We have granted you (O Muhammad) A manifest victory." (48.1)