Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
Bukhari :: Book 6 :: Volume 60 :: Hadith 379
Narrated Abdullah:
Regarding the Verses: 'And was at a distance of but two bow-lengths or (even) nearer; So did (Allah) convey the Inspiration to His slave (Gabriel) and then he Gabriel) conveyed (that to Muhammad...' (53.9-10) Ibn Mas'ud narrated to us that the Prophet had seen Gabriel with six hundred wings.