At the time of the birth of Christianity, only in one portion of the Roman world could a new and pure religion have arisen. The fusion of the empire had, by destroying their national basis, fatally weakened the Pagan religions; so far as real feeling was concerned, they had passed into the hands of the ignorant classes exclusively, and had lost the vitality in which alone the higher religious forces can germinate. Philosophies, resting on a common basis of contempt of the popular polytheism, were the refuge of the more enlightened. Between philosophers and those who still believed in the power of the ancient gods there existed a vast mass of people who had religious instincts with no sure means of satisfying them, ripe subjects for the new religion which they looked for but could not originate. At this time, throughout the Pagan world, a high and systematic morality could only be reared on an intellectual basis which destroyed sympathy with common men; in no part of it could have been developed the pure enthusiasm needed for the founding of a great religion.
One region of the empire alone was free from the symptoms of religious decay. In the small district of Palestine, with many offshoots scattered over the world, lived a people who professed a religion of the purest type. And this religion was not a lightly held philosophical theory; its adherents clung to it with a passionate tenacity, and were ever ready to face martyrdom in its defence. It was a pure monotheism, and morality was inculcated by it, indeed, maintained by it, in the strongest and most effective fashion. With justice Josephus could assert that Greek philosophers only followed the example of his countrymen, and taught doctrines which the Jewish sacred law had made practical realities.[1] For Judaism was not an esoteric creed which only the more cultured Jews fully understood; the lowest of the people grasped its principles, abhorred the idea of polytheism, detested even the smallest advance towards idolatry, and regarded every sin as a violation of divine decrees. Such a religion, pure and strongly held, was fit to be the parent of a noble religious system. In it originated the earliest doctrines of the religion which now sprang from it and conquered the Roman world. And as Judaism was in a special sense a national religion, its development must be examined in the history of the Jewish people.