Muslims believe the Quran was orally revealed by God to the final Islamic prophet Muhammad through the angel Gabriel incrementally over a period of some 23 years, beginning on the Night of Power, when Muhammad was 40, and concluding in 632, the year of his death. Muslims regard the Quran as Muhammad's most important miracle, a proof of his prophethood, and the culmination of a series of divine messages starting with those revealed to the first Islamic prophet Adam, including the Islamic holy books of the Torah, Psalms, and Gospel.