"When he was about forty 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 the prophetic tradition earlier codified in Judaism and Christianity; to warn his compatriots of the impending Judgement Day; and to castigate social injustices of his city.