But popular Islam has always been susceptible to the idea of the Mahdi — "the guided one" — the just ruler who shall arise in the end of time and fill the earth with equity and justice as it has been filled with tyranny and oppression. Remembering that, as I have already mentioned, according to other traditions, Jesus was to appear as an upright Judge and just Imam, remit the Jizya, and so on, the presumption is that the figure of the Mahdi is the adaptation of the figure of the millennial Christ, or that, at any rate, the political desire for a just Caliph decked itself out with these eschatological ideas. Other details which are associated with the Mahdi appear also associated with the appearance of Jesus such as the great rain, the great productivity of the earth, and the cheapness and plenty of everything. That the adaptation took place in the time of the Abbaside propaganda is perhaps shown by the traditions which declare that the Mahdi will come of the Prophet's house or by the following which definitely associates the coming of the Mahdi with the Abbaside rising which began in Khurasan.

"A people will come out of the East and will smooth the way for the Mahdi."¹

"The Messenger of God said: Three will fight over your Treasures. They will not become the property of any of them. Then will appear the black flags from the direction of the East. They will make such slaughter of you as was not made by any people. Then, says the narrator, he mentioned something which I have not remembered.

Then he said: "When you see him, swear allegiance to him even if you have to creep upon the snow. For he is the vice-gerent of God — the Mahdi."¹

These things which I have mentioned found their way into Islam by way of the mind of the people. They, of course, affected Moslem theology, for theology had to find a place for what had become so deeply rooted in the mind of the Moslem populace. But there was also a direct influence of Christian theology upon the thought of the younger religion. As showing how that took place I take two things which occur in the works of John of Damascus. John's father was a Christian who was employed in an official position at the court of the Omayyad caliphs at Damascus. He himself in early life occupied a similar position, and began his literary activity there before he withdrew to the monastery of Saba where the latter part of his life was spent. In the introduction to his great dogmatic work in which he treats of the heresies he devotes a section to Islam. There is also included in his works a Dialogue with a Saracen which is a kind of manual for the guidance of Christians in their arguments with Muhammadans. It is not the only work of that kind which has come down to us from that early time. It is not perhaps so interesting as we might expect from the situation to which it belongs. But the very fact of such a work having been composed is itself suggestive. It proves what in itself is inherently likely — that arguments of that kind were fairly frequent. It