4. The concept of monotheism. The Greco-Roman world was honeycombed with polytheism. The Greeks were reputed to have 30,000 gods, most of them gods of lust. In fact, the gods were more immoral than the men who worshiped them. By the time of Plato the idea of one supreme God was discussed by the philosophers, but the common people continued with their idolatry. Many a seeking Greek, fed up with the immorality of the Olympian gods and disillusioned with the speculations of the pagan philosophers, turned with a sigh of relief to the ethical monotheism of Judaism, which preached the doctrine of one true God, Creator of heaven and earth, immanent and yet transcendent, mighty and yet merciful, who punishes sin and rewards virtue. No other religion had such an exalted doctrine. This was an immense stimulus toward attracting converts.
5. The practice of morality. Immorality ranked with idolatry as the two great sins of the pagan world. Its large cities were cesspools of iniquity. Divorce was widespread; infanticide was common. Paul’s description of pagan society in Romans 1 is an accurate picture of the moral decadence of the Roman Empire. Tenney describes it graphically:
Paganism was devoid of any power to lift it above itself, and the growing consciousness of its own impotence brought upon it a pessimism and a depression that it could not escape. Corruption in politics, debauchery in pleasure, fraud in business, deceit and superstition in religion made life in Rome depressing for the many and unendurable for the few.
In contrast to this corruption was the wholesome domestic life of the Jewish people. Divorce was a rare occurrence. Children were regarded as a gift from God; consequently family life was sacred. Fathers taught the Law to their families, and every boy became a Son of the Law at thirteen years of age. Fathers also taught their sons a trade. Immorality was frowned on, with adultery punishable by death. Heathen families desirous of escaping the moral pollution of pagan society found a warm and welcome change in the high moral standards of Judaism. This too was a great drawing card.
6. The promise of a coming Savior. In the closing centuries of the pre-Christian era there was in the Greco-Roman world an almost universal longing for a deliverer. The Greeks gave the world its greatest philosophers and Rome provided its greatest statesmen; but neither the lucubrations of the one nor the machinations of the other could solve the problems of society. Plato had suggested in The Republic that philosophers should be kings and kings should be philosophers; but there were few takers for his recipe, because as a rule philosophers don’t make good kings and kings don’t make good philosophers. Confucius tried it and failed. And even the philosophers were unable to live up to their own high standards. Consequently the man in the street, far removed from both philosopher and statesman, looked in vain for someone who could promise-and provide-the abundant life both here and hereafter.
Into this vacuum stepped the Jews with their centuries-old expectation of a coming Messiah. There was nothing vain or vague about this Figure. Both His person and His program were clearly outlined in the Hebrew Scriptures. He would be Prophet, Priest, and King, all in one. He would succeed where others had failed. Possessed of divine power and knowledge, He would establish a kingdom of universal peace based on absolute justice-something the world had dreamed of but never seen.
The Greco-Roman world listened, and liked what it heard. Thus Judaism became a missionary religion and helped prepare the way for Christianity.