In other words, he is intelligent enough to believe in God; and the Moslem, the man of the desert, is intelligent enough to believe in God.
But his belief is lacking in that humane complexity that comes from comparison.

The man looking at the palm-tree does realise the simple fact that God made it; while the man looking at the lamp-post in a large modern city can be persuaded by a hundred sophistical circumlocutions that he made it himself.

But the man in the desert cannot compare the palm-tree with the lamp-post, or even with all the other trees which may be better worth looking at than the lamp-post.

Hence his religion, though true as far as it goes, has not the variety and vitality of the churches that were designed by men walking in the woods and orchards.
I speak here of the Moslem type of religion and not of the oriental type of ornament, which is much older than the Moslem type of religion.
But even the oriental type of ornament, admirable as it often is, is to the ornament of a gothic cathedral what a fossil forest is to a forest full of birds.

In short, the man of the desert tends to simplify too much, and to take his first truth for the last truth.
And as it is with religion so it is with morality.