How Revelation came

Narrated Aisha, the mother of the faithful believers: Al-Harith bin Hisham asked Allah's apostle: 'O Allah's apostle. How is the divine inspiration revealed to you?' Allah's apostle replied, 'Sometimes it is "revealed" like the ringing of a bell, this form of inspiration is the hardest of all and then this state passes off after I have grasped what is inspired. Sometimes the Angel comes in the form of a man and talks to me and I grasp whatever he says'. [Bukhari, I, No. 2.]