The Islamic prophet Muhammad was born and lived in Mecca for the first 52 years of his life (570–622 A.D.) Orphaned early in life, he became known as a prominent merchant, and as an impartial and trustworthy arbiter of disputes. He married his first wife, the 40-year-old widow Khadijah at age of 25. He would also marry Aisha later in his life. Islamic scholars debate her age but are agreed that she was in her teenage years. Her marriage is in Sahih Bukhari Volume 7, Book 62, Number 18. According to the Muslim tradition, Muhammad began receiving revelations at the age of 40. The key themes of his messages in Mecca were the oneness of God and the rejection of polytheism, generosity towards the poor and the needy, kind treatment and emancipation of slaves, and the equality between men and women before God. Some of his peers respected his words and became his followers. Many others, including tribal leaders, opposed, ridiculed and eventually boycotted his clan, and Muhammad and his followers were harassed, assaulted, tortured and forced into exile. Several attempts were made on his life. When his uncle and chief protector, Abu Talib, who was the head of the clan of Banu Hashim died, Muhammad migrated to Medina in 622, where he had many followers who agreed to help and assist him.