Soon the angel appeared to him a second time, and gave him an assurance that he was not possessed by demons but called of God to spread the revelations of heaven. Mohammed now believed and announced that Allah, the lord of heaven and earth, had chosen him as his ambassador to inform men of his holy will; he now believed and taught that the Lord spake by him, and that his utterances were inspirations and revelations from the only and most high God, and being written down separately and eventually put together in the sacred book _Koran_,[c] they were so regarded by the faithful and accepted with reverence. Thus began Mohammed’s prophetic career in the year 610 or 612 of our era. Like the seers of old, like the prophets in Israel, he took the enthusiasm which dwelt in him as a “charge from the Lord,” and the words which issued from his mouth as the outpourings of the divine spirit. Convinced of the truth of his prophetic mission, Mohammed now entered on his office of teacher. But with all his devotion to the holy cause he went to work with great caution. He first turned to his kinsmen that he might be recognised by them as the messenger of God. His wife Khadija, his daughters, his cousin Ali, the ten-year-old son of Abu Talib, his friend Abu Bekr, a well-to-do merchant of upright character and clear discernment, and his former slave Zaid to whom he had given his liberty were his first converts. In like manner he avoided anything which might have irritated his compatriots. “He sought to bring his teaching into harmony with their prejudices and to lead them gradually to a better knowledge. He did not venture to attack the sanctity of the Kaaba, joined in the ceremonies of the pilgrim festival, and sanctioned the adoration of the Black Stone.” Thus three years went by, during which the number of Mohammed’s adherents did not exceed forty, for the most part young men, foreigners or slaves. It was not till the fourth year that in accordance with another vision he attempted to appear publicly in the character of a prophet. He first addressed himself to the men of his own race, the Koreish; and in the name of the one God who had sent him as his apostle, threatened them with the fire of hell if they did not renounce their unbelief. “One day ye shall die and rise again; then must ye give account of your deeds and shall be rewarded for your virtue in paradise and punished for your vices in hell.”