Born approximately 570 CE (Year of the Elephant) in the Arabian city of Mecca, Muhammad was orphaned at the age of six. He was raised under the care of his paternal grandfather Abd al-Muttalib, and upon his death, by his uncle Abu Talib. In later years he would periodically seclude himself in a mountain cave named Hira for several nights of prayer. When he was 40, Muhammad reported being visited by Gabriel in the cave, and receiving his first revelation from God. Three years later, in 610, Muhammad started preaching these revelations publicly, proclaiming that "God is One", that complete "submission" (islām) to God is the right way of life (dīn), and that he was a prophet and messenger of God, similar to the other prophets in Islam.