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"And those who disbelieved will be driven to Hell in groups, till, when they reach it, the gates thereof will be opened (suddenly like a prison at the arrival of the prisoners), And its keepers will say, "Did not the Messengers come to you from yourselves, reciting to you the Verses of your Lord, and warning you of the Meeting of this Day of yours?" They will say: "Yes, but the Word of torment has been justified against the disbelievers!"" [Az-Zumar (39):71]

Narrated 'Aa'ishah: (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." 'Aa'ishah added: Verily I saw the Prophet being inspired Divinely on a very cold day and noticed the Sweat dropping from his forehead (as the Inspiration was over). [The Book of Revelation Volume 1, Book 1, Hadeeth 2]