#FultonFridays: Mary and the Muslims

On Fridays, I post excerpts from the writings of the great American bishop and media evangelist, Ven. Fulton J. Sheen. I call them #FultonFridays.
Moslemism is the only great post-Christian religion of the world. Because it had its origin in the seventh century under Mohammed, it was possible to unite, within it, some elements of Christianity and of Judaism, along with particular customs of Arabia. Moslemism takes the doctrine of the unity of God, His majesty and His creative power, and uses it, in part, as a basis for the reproduction of Christ, the Son of God. Misunderstanding the notion of the Trinity, Mohammed made Christ a prophet announcing Him just as to Christians, Isaiah and John the Baptist are prophets announcing Christ.
The Christian European West barely escaped destruction at the hands of the Moslems. At one point they were stopped near Tours and at another point, later on in time, outside the gates of Vienna. The Church throughout northern Africa was practically destroyed by Moslem power, and at the present hour, the Moslems are beginning to rise again.
If Moslemism is a heresy, as Hiliaire Belloc believes it to be, it is the only heresy that has never declined. Others have had a moment of vigor, then gone into doctrinal decay at the death of the leader, and finally evaporated in a vague social movement. Moslemism, on the contrary, has only had its first phase. There was never a time in which it declined, either in numbers, or in the devotion of its followers.
The missionary effort of the Church toward this group has been at least on the surface, a failure, for the Moslems are so far almost unconvertible. The reason is that for a follower of Mohammed to become a Christian is much like a Christian becoming a Jew. The Moslems