vast empire of the Caliphate, from its starting point in Arabia, spread in eighty years from the Oxus River to the Atlantic Ocean.[1183] The rapid rise and spread between 1745 and 1803 of the Wahaby clan and sect, the Puritans of Islam, which resulted for a time in their political and religious domination of much of Arabia from their home in the Nejd, recalls the stormy conquests of Mohammed’s followers.  Islam is to-day a persistent source of ferment in Algeria, the Sahara, and the Sudan, On the other hand.  Buddhism serves to cement together the diverse nomadic tribes of the Central Asia plateaus, and keep them in spiritual subjection to the Grand Lama of Lhassa.  The Chinese government makes political use of this fact by dominating the Lama and employing him as a tool to secure quiet on its long frontier of contact with its restless Mongol neighbors.  Moreover the religion of Buddha has restrained the warlike spirit of the nomads, and by its institution of celibacy has helped keep down population below the boiling-point. [Compare maps pages 484 and 513.]

[Sidenote:  The faith of the desert.]

The faith of the desert tends to be stern, simple and austere.  The indulgence which Mohammed promised his followers in Paradise was only a reflex of the deprivation under which they habitually suffered in the scant pastures of Arabia.  The lavish beauty of the Heavenly City epitomized the ideals and dreams of the desert-stamped Jew.  The active, simple, uncramped life of the grasslands seems essential to the preservation of the best virtues of the desert-bred.  These disappear largely in sedentary life.  The Bedouin rots when he takes root.  City life contaminates, degrades him.  His virile qualities and his religion both lose their best when he leaves the desert.  Contact with the cities of Philistia and the fertile plains of the Canaanites, with their sensual agricultural gods, demoralized the Israelites.[1184] The prophets were always calling them back to the sterner code of morals and the purer faith of their days of wandering.  Jeremiah in despair holds up to them as a standard of life the national injunction of the pastoral Rechabites, “Neither shall ye build house nor sow corn nor plant vineyard, but all your days ye shall dwell in tents."[1185] The ascent in civilization made havoc with Hebrew morals and religion, because ethics and religion are the finest and latest flower of each cultural stage.  Transition shows the breaking down of one code before the establishment of another.

Judaism has always suffered from its narrow local base.  Even when transplanted to various parts of the earth, it has remained a distinctly tribal religion.  Intense conservatism in doctrine and ceremonial it still bears as the heritage of its desert birth.  Islam too shows the limitations of its original environment.  It embodies a powerful appeal to the peoples of arid lands, and among these it has spread and survives as an active principle.  But it belongs to an arrested economic and social development, lacks the germs of moral evolution which Christianity, born in the old stronghold of Hebraic monotheism, but impregnated by all the cosmopolitan influences of the Mediterranean basin and the Imperium Romanum, amply possesses.