`A'isha told that al-Harith b. Hisham asked God's messenger, "How does the inspiration come to you, messenger of God?" to which he replied, "It comes to me at times like the clanging of a bell, and that is the type which is most severe for me; it then leaves me, I having retained of it what the angel said. At times the angel appears to me in human form and speaks to me, and I retain what he says." `A'isha said she had seen the inspiration descending on him on a very cold day, and his forehead pouring with sweat when it left him.
(Bukhari and Muslim.)