When Rasulullah was forty years old, an angel appeared in the cave of Hira (Jabl-e-Noor) and commanded him to 'Read' Rasulullah replied that he could not. At this, the angel firmly embraced Rasulullah and released him. He again commanded him to 'Read' and again Rasulullah replied that he couldn't. He was embraced again and released. For the third time the angel commanded him to 'Read' and again Rasulullah replied that he could not read. The angel then said:
'Read, in the name of Allah who created (everything). He created man from a clot of blood. Read, your Lord is Great who taught you but virtue of the pen that which you did not know'. The angel then disappeared.
This Divine incident so affected Rasulullah that he hurried home where he asked his beloved wife Hazrat Khadeejah (R.A.) to cover him with a blanket. When he had calmed down sufficiently, he related the incident to Hazrat Khadeejah (R.A.) who comforted him with words of praise, wisdom and encouragement.
When Rasulullah said he was afraid for his life, Hazrat Khadeejah (R.A.) consoled him with the words: 'No, no. On the contrary, you should feel happy. Allah will never forsake you because you have been loving, helpful, truthful, and you possess the sublime character which no other man possesses, and you are 'JUST'.
Hazrat Khadeejah (R.A.) took Rasulullah to her cousin Waraqah-bin-Nawfal, who at once confirmed the signs of prophethood and he stressed that Rasulullah would be persecuted by his own people. Inspite of this warning Rasulullah continued to visit the Cave of Hira (Jabl-e-Noor).
After this granting of apostleship, Rasulullah began to preach Islam. The first man to become a Muslim was his closest friend Hazrat Abu Bakr (R.A.) and first women was his beloved wife Hazrat Khadeejah (R.A.. Others who became Muslims willingly were Hazrat Ali-ibn-Abu Taalib (R.A.) the young cousin of Rasulullah , and Hazrat Zaid-bin-Harith (R.A.) the freed slave of Rasulullah.
The influence of Hazrat Abu Bakr (R.A.) was so strong that all his associates embraced Islam at his request. Among them were Hazrat Uthmaan-ibn-Affan (R.A.), and Hazrat Abdul Rahmaan-bin-Auf (R.A.), and Hazrat Zubayr-bin-Awwam (R.A.).