At the age of 40, while engaged in a meditative retreat, he received his first revelation from God through the Archangel Gabriel. This revelation, which continued for twenty-three years, is known as the Qur’ān. The Prophet Muhammad began to recite the words he heard from Gabriel and to preach the truth which God had revealed to him. The people of Makkah were stepped in their ways of ignorance and opposed him and his small group of followers in every way. These early Muslims suffered bitter persecution. In the year 622 C.E., God gave the Muslim community the command to emigrate. This event, the hijrah or migration, in which they left Makkah for the city of Madīnah, some 260 miles to the North, marks the beginning of the Muslim calendar.
Madīnah provided the Prophet Muhammad and the Muslims the safe and nurturing haven in which the Muslim community grew and here he established the Islāmic state. After several years, the Prophet and his followers returned as conquerors. He was now supreme ruler of Arabia cleansing the land from idolatry and dedicated the Ka’bāh to the worship of the One God. He died at the age of 63 and within a century of his death, Islām had spread to Spain in the west and as far east as China.