Mishkat al-Masabih 584
Ibn Shihab said that ‘Umar b. ‘Abd al-‘Aziz postponed the afternoon prayer somewhat and 'Urwa said to him, “Gabriel has come down and prayed in front of God’s Messenger.” So ‘Umar said to him, “Be sure of what you are saying, ‘Urwa.” He replied:
“I heard Bashir b. Abu Mas'ud say that he heard Abu Mas'ud say that he heard God’s
 Messenger say, 'Gabriel came down and acted as my imam and I prayed along with him, then I prayed along with him, then I prayed along with him, then I prayed along with him, then I prayed along with him,’ reckoning with his fingers five times of prayer." 

(Bukhari and Muslim.)
وَعَن ابْنِ شِهَابٍ أَنَّ عُمَرَ بْنَ عَبْدِ الْعَزِيزِ أَخَّرَ الْعَصْرَ شَيْئًا فَقَالَ لَهُ عُرْوَةُ: أَمَا إِنَّ جِبْرِيلَ قَدْ نَزَلَ فَصَلَّى أَمَامَ رَسُولِ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَقَالَ لَهُ عُمَرُ: اعْلَمْ مَا تَقُولُ يَا عُرْوَةُ فَقَالَ: سَمِعْتُ بَشِيرَ بْنَ أَبِي مَسْعُودٍ يَقُولُ سَمِعْتُ أَبَا مَسْعُودٍ يَقُولُ: سَمِعْتُ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ يَقُولُ: «نَزَلَ جِبْرِيلُ فَأَمَّنِي فَصَلَّيْتُ مَعَهُ ثُمَّ صَلَّيْتُ مَعَهُ ثُمَّ صَلَّيْتُ مَعَهُ ثُمَّ صَلَّيْتُ مَعَهُ ثُمَّ صَلَّيْتُ مَعَهُ» يحْسب بأصابعه خمس صلوَات