Allah's Divine Inspiration touches Muhammad s.a.w

For years after his marriage, Muhammad had been accustomed to secluding himself in a cave in Mount Hira, a few miles from Mecca. To this cave he used to go for prayer and 
meditation, sometimes alone and sometime with his family. There, he often spent the whole nights in deep thought and profound communion with the Unseen yet All-Knowing Allah of the Universe. It was during one of those retirements and in the still hours of the night, when no human sympathy was near, that an angel came to him to tell him that he was the Messenger of Allah sent to reclaim a fallen people to the knowledge and service of their Lord.

Renowned compilers of authentic traditions of Islam agree on the following account of the first
revelations received by the Prophet.

Muhammad would seclude himself in the cave of Mount Hira and worship three days and nights. He would, whenever he wished, return to his family at Mecca and then go back again, taking wihim the necessities of life. Thus he continued to return to Khadijah from time to time until one day the revelation came down to him and the Angel Gabriel (Jibreel) appeared to him and said:

"Read!"

But as Muhammad was illiterate, having never received any instruction in reading or writing, he said to the angel:

"I am not a reader."
The angel took a hold of him and squeezed him as much as he could bear, and then said again:

"Read!"
Then Prophet said:
"I am not a reader."
The Angel again seized the Prophet and squeezed him and said:

"Read! In the Name of Your Lord, Who has created (all that exists), has created a man from a
clot (a piece of thick coagulated blood). Read! And your Lord is the Most Generous, Who has
taught (the writing) by the pen, has taught man that which he knew not." (Ch 96:1-4 Quran).
Then the Prophet repeated the words with a trembling heart. He returned to Khadijah from Mount Hira and said: "Wrap me up! Wrap me up!" She wrapped him in a garment until his fear was dispelled. He told Khadijah what had occurred and that he was becoming either a soothsayer or one smitten with madness. She replied: "Allah forbid! He will surely not let such a thing happen, for you speak the truth, you are faithful in trust, you bear the afflictions of the people, you spend in good works what you gain in trade, you are hospitable and you assist your fellow men. Have you seen anything terrible?" Muhammad replied: "Yes," and told her what he had seen.

Whereupon, Khadijah said: "Rejoice, O dear husband and be cheerful. He is Whose hands stands Khadijah's life bears witness to the truth of this fact, that you will be the prophet to this people."