Sahih Muslim 177 d
Masruq reported:
I said to 'A'isha: What about the words of Allah:" Then he drew nigh and came down, so he was at a distance of two bows or closer still: so He revealed to His servant what He revealed" (al-Qur'an, liii. 8-10)? She said: It implies Gabriel. He used to come to him (the Holy Prophet) in the shape of men; but he came at this time in his true form and blocked up the horizon of the sky.
وَحَدَّثَنَا ابْنُ نُمَيْرٍ، حَدَّثَنَا أَبُو أُسَامَةَ، حَدَّثَنَا زَكَرِيَّاءُ، عَنِ ابْنِ أَشْوَعَ، عَنْ عَامِرٍ، عَنْ مَسْرُوقٍ، قَالَ قُلْتُ لِعَائِشَةَ فَأَيْنَ قَوْلُهُ ‏{‏ ثُمَّ دَنَا فَتَدَلَّى * فَكَانَ قَابَ قَوْسَيْنِ أَوْ أَدْنَى * فَأَوْحَى إِلَى عَبْدِهِ مَا أَوْحَى‏}‏ قَالَتْ إِنَّمَا ذَاكَ جِبْرِيلُ صلى الله عليه وسلم كَانَ يَأْتِيهِ فِي صُورَةِ الرِّجَالِ وَإِنَّهُ أَتَاهُ فِي هَذِهِ الْمَرَّةِ فِي صُورَتِهِ الَّتِي هِيَ صُورَتُهُ فَسَدَّ أُفُقَ السَّمَاءِ ‏.‏