"The main difference between the Vedic and Avestan religions is that in the latter the Vedic worship of natural powers and phenomena is superseded by a more ethical and personal interest. Ahura-Mazda (Ormazd), the living wisdom, replaces Indra, the lightning-god. In Iran there grew up, what India never saw, a consciousness of world-purpose, ethical and spiritual; a reference of the ideal to the future rather than the present; a promise of progress; and the idea that the law of the universe means the final deliverance of good from evil, and its eternal triumph." [1] [Footnote 1: Samuel Johnson's Religion of Persia.] The loftiness which modern scholars like Haug, Lenormant, and Spiegel see in the Zend-Avesta pertains more directly to the earlier portions of these sacred writings, attributable to Zoroaster, called the Gâthâs. But in the course of time the Avesta was subjected to many additions and interpretations, called the Zend, which show degeneracy. A world of myth and legend is crowded into liturgical fragments. The old Bactrian tongue in which the Avesta was composed became practically a dead language. There entered into the Avesta old Chaldaean traditions. It would be strange if the pure faith of Zoroaster should not be corrupted after Persia had conquered Babylon, and even after its alliance with Media, where the Magi had great reputation for knowledge. And yet even with the corrupting influence of the superstitions of Babylon, to say nothing of Media, the Persian conquerors did not wholly forget the God of their fathers in their old Bactrian home. And it is probable that one reason why Cyrus and Darius treated the Jews with so much kindness and generosity was the sympathy they felt for the monotheism of the Jewish religion in contrast with the polytheism and idolatry of the conquered Babylonians. It is not unreasonable to suppose that both the Persians and Jews worshipped substantially the one God who made the heaven and the earth, notwithstanding the dualism which entered into the Persian religion, and the symbolic worship of fire which is the most powerful agent in Nature; and it is considered by many that from the Persians the Jews received, during their Captivity, their ideas concerning a personal Devil, or Power of Evil, of which no hint appears in the Law or the earlier Prophets. It would certainly seem to be due to that monotheism which modern scholars see behind the dualism of Persia, as an elemental principle of the old religion of Iran, that the Persians were the noblest people of Pagan antiquity, and practised the highest morality known in the ancient world. Virtue and heroism went hand in hand; and both virtue and heroism were the result of their religion. But when the Persians became intoxicated with the wealth and power they acquired on the fall of Babylon, then their degeneracy was rapid, and their faith became obscured. Had it been the will of Providence that the Greeks