At the age of 40, while engaged in a meditative retreat, Muhammad received his first revelation from God through the Archangel Gabriel. This revelation, which continued to descend over a period of twenty-three years, is known as the Quran.
Muhammad began to share the revelations he received from God with the people of Makkah. Being idol worshippers, the general populace rejected Muhammad’s call to worship only one God. They opposed him and his small group of followers in every way possible, some suffering bitter forms of persecution and even torture.
In 622 CE, God gave the community of believers the command to emigrate. This event, known as the hijrah, or migration, in which they left Makkah for the blessed city of Madinah (some 260 miles to the north), marks the beginning of the official Muslim calendar.
The city of Madinah provided the new community of Muslims a safe and nurturing abode in which they could practice their faith without the spite of persecution. After several years, the Prophet and his followers returned to Makkah, peacefully claiming the city and forgiving their enemies. Then, turning their attention to the Ka’bah (the sanctuary that Prophet Abraham had previously built), they removed the idols and rededicated the sanctuary to the worship of the One God. By the time of the Prophet’s passing, at the age of 63 (may God bless him and grant him peace), most of the people of Arabia had embraced the Prophet’s message, and in less than a century thereafter, Islam rapidly spread to Spain in the west, and as far as China in the east.