When the prophet was twenty-five years old, his uncle secured for him a position with a caravan owned by a wealthy widow, Khadija. Thanks to Mohammed's keen business sense the caravan was highly successful, and he was induced to personally report his success to Khadija. That lady, a wealthy widow of forty years, and the mother of three children, was highly pleased at Mohammed's story. As she listened to the proof of his business ability and fondly scanned his large, nobly formed head, his curling coal-black hair, his piercing eyes, and his comely form, it naturally occurred to her that this vigorous and handsome young fellow would make an excellent successor to her deceased husband. She had her way and they were married. During the next fifteen years Mohammed led a tranquil life. His future was provided for and he had plenty of leisure to occupy himself as he chose. In these years Mohammed and his wife continued to be conventional worshipers of idols, who nightly performed rites in honor of various gods and goddesses, among whom were Allah and his female consoler Al-Lat. And so, by the year 610, Mohammed, at the age of forty, was nothing more than a respectable but unknown tradesman who had experienced no extraordinary crises, whose few existing utterances were dull and insipid, and whose life seemed destined to remain as insignificant and unsung as any other Arab's. At this time, he began to retire for days at a time to a cave in the foothills of Mount Hira, a hill several miles north of Mecca. Meanwhile his business languished. As the months passed, he still continued to act in the same incomprehensible manner; it was noticed that little by little certain members of his immediate family attended him to his refuge or gathered with him in some one of their houses. This continued for several years until it was rumored that Mohammed, the camel driver, was confidently claiming the honor of having made a great discovery; namely, that "There is no God but Allah, and Mohammed is His Prophet." By what process of thought had Mohammed come to exalt Allah not merely above all Arabian gods, but above the gods of all times? Furthermore, why was he so certain of his own intimate association with Allah? We can understand this if we consider Mohammed in the light of a victim of mental disease. One account informs us that as Mohammed was wandering near the cave at Mount Hira, "an angel from the sky cried to him, 'O Mohammed, I am Gabriel!'" He was terrified and hurried home to impart his experience to his wife.