"In Arabia there shall be but one religion" is reported by Tradition as a word of the dying Prophet, and he himself had certainly given example by his expulsion of the Jews from Medina. Probably, however, no great measures of expulsion were necessary in the time of Omar. The only definite case mentioned is that of the Christians of Najran, consecrated to Christianity though that district was by the persecution suffered under Dhu Nuwas. Lands were given them in exchange elsewhere. Some migrated to Syria, but the greater part settled in the vicinity of Kufa.¹

That seems, however, to have been an exception. The Arabs within the Peninsula seem to have gone over from Christianity to Islam without much hesitation or regret. The same applies very largely to the Arabs of Syria. The House of Ghassan, long the bulwark of the Roman Empire and of Christianity on the Syrian border, adopted Islam almost at once. "They were Lords in the days of Ignorance and Stars in Islam."² In the Euphrates district attachment to Christianity seems to have been stronger. We hear of several nomad tribes which remained Christian. In fact there was a Bishop of the nomad Arabs a considerable time after the Arab conquest, which shows that the defection was not complete. Still, on the whole, it seems to be true that the nomad Arabs, both within the Peninsula and on its borders, went over to Islam very easily, especially when the success of its

arms began to appear. After the great victory of Qadisiyyah, some of the Christian Arab tribes came to Sa'd, the victorious general, and said, "The tribes which at first embraced Islam were wiser than we. Now that Rustam hath been slain all will accept the new belief." So there came over many tribes in a body and made profession of the faith.¹ The attachment even of the nominally Christian tribes to that faith had probably never been very deep, and they could have had but a very superficial understanding of it. Indeed, what interest could the abstruse questions of Christology, about which the Eastern Church had been kept in a ferment for centuries, have had for them? The formulæ of doctrine could at most have been for the ordinary populations even of the settled countries little more than slogans of party warfare; if they were not also symbols of national spirit protesting against imperial rule under the form of the Orthodox Faith.

Now, at any rate to the Arabs, had come a stronger call of nationality. Religiously — if they were religiously inclined — Islam probably gave them all that they required. It was Monotheistic, and it reformed with a strong hand the worst moral abuses of Paganism. In place of the abstruse speculations as to the nature of God and the relation of the divine to the human with which the attention of the Church had been so largely taken up in its Trinitarian and Christological controversies, Islam harked back to the idea of a God of power and of moral will, express-