great revolution wrought by God himself, a catastrophic intervention such as the prophets had so often foretold. Meanwhile, however, the Jews had a twofold task in preparation for that great event; first, to make the reign of God a reality for themselves individually and as a people; and, second, to make known to the Gentiles the true God and his righteous will and convert them to the true religion. This conception of the prophetic mission of Israel among the nations had been set forth by the prophet in Isaiah 42 and 49: Israel is to be a light to the nations, that God's salvation may reach to the end of the earth; and not only reflection but the logic of the situation led to the same result. In the two or three centuries on either side of the Christian era Judaism made great numbers of converts throughout the wide dispersion. Various Oriental religions in that age were offering the secret and the assurance of a blessed immortality through initiation into their mysteries, and drew into their mystic societies many seekers of salvation. Judaism on the contrary, as we have seen, appeared to ancient observers to be not a mystery but a philosophy. It had a high doctrine about God which was publicly taught in its synagogue schools, a rule of life, and venerable scriptures in which both the doctrine and the rule were contained; and it sought to make converts by rational persuasion. In this aspect Judaism is sometimes called