he was about 40 years old, he began receiving at mount Hira' what Muslims regard as divine revelations delivered through the angel Gabriel, which would later form the Quran. These inspirations urged him to proclaim a strict monotheistic faith, as the final expression of Biblical prophetism earlier codified in the sacred texts of Judaism and Christianity; to warn his compatriots of the impending Judgement Day; and to castigate social injustices of his city. Muhammad's message won over a handful of followers (the ṣaḥāba) and was met with increasing opposition from Meccan notables. In 622 CE, a few years after losing protection with the death of his influential uncle ʾAbū Ṭālib ibn ʿAbd al-Muṭṭalib, Muhammad migrated to the city of Yathrib (subsequently called Medina) where he was joined by his followers. Later generations would count this event, known as the hijra, as the start of the Islamic era. In Yathrib, where he was accepted as an arbitrator among the different communities of the city under the terms of the Constitution of Medina, Muhammad began to lay the foundations of the new Islamic society, with the help of new Quranic verses which provided guidance on matters of law and religious observance. The surahs of this period emphasized his place among the long line of Biblical prophets, but also differentiated the message of the Quran from the sacred texts of Christianity and Judaism. Armed conflict with the Arab Meccans and Jewish tribes of the Yathrib area soon broke out. After a series of military confrontations and political manoeuvres, Muhammad was able to secure control of Mecca and allegiance of the Quraysh in 629 CE. In the time remaining until his death in 632 CE, tribal chiefs across the Arabian peninsula entered into various agreements with him, some under terms of alliance, others acknowledging his claims of prophethood and agreeing to follow Islamic practices, including paying the alms levy to his government, which consisted of a number of deputies, an army of believers, and a public treasury. In Islam, "the Qurʾān is conceived by Muslims to be the word of God spoken to Muḥammad and then passed on to humanity in exactly the same form as it was received". While the Quran doesn't dwell on politics, it does make mention of concepts such as "the oppressed" (mustad'afeen), "emigration" (hijra), the "Muslim community" (Ummah), and "fighting" or "struggling" in the way of God (jihād), that