After his decease there remained not one of the followers of the prophet that did not apostatize, saving only a small company of his “Companions” and kinsfolk, who hoped thus to secure the government to themselves.  Hereupon Abu Bekr displayed marvelous skill, energy, and address, so that the power passed into his hands....  And thus he persevered until the apostate tribes were all brought back to their allegiance, some by kindly treatment, persuasion, and craft; some through terror and fear of the sword; and others by the prospect of power and wealth as well as by the lusts and pleasures of this life.  And so it came to pass that all the Bedouin tribes were in the end converted outwardly, but not from inward conviction.[39]

[Sidenote:  The Arabs thus reclaimed were, at the first, sullen.] The temper of the tribes thus reclaimed by force of arms was at the first strained and sullen.  But the scene soon changed.  Suddenly the whole peninsula was shaken, and the people, seized with a burning zeal, issued forth to plant the new faith in other lands.  It happened on this wise: 

[Sidenote:  Roused by war-cry, they issue from the peninsula, A.D. 634, et. seq. The opposing forces.  Arab enthusiasm.] The columns sent from Medina to reduce the rebellious tribes to the north-west on the Gulf of Ayla, and to the north-east on the Persian Gulf, came at once into collision with the Christian Bedouins of Syria on the one hand and with those of Mesopotamia on the other.  These again were immediately supported by the neighboring forces of the Roman and Persian empires, whose vassals respectively they were.  And so, before many months, Abu Bekr found his generals opposed by great and imposing armies on either side.  He was, in fact, waging mortal combat at one and the same moment with the Kaiser and the Chosroes, the Byzantine emperor and the great king of Persia.  The risk was imminent, and an appeal went forth for help to meet the danger.  The battle-cry resounded from one end of Arabia to the other, and electrified the land.  Levy after levy, en masse, started up at the call from every quarter of the peninsula, and the Bedouin tribes, as bees from their hive, streamed forth in swarms, animated by the prospect of conquest, plunder, and captive damsels, or, if slain in battle, by the still more coveted prize of the “martyr” in the material paradise of Mohammed.  With a military ardor and new-born zeal in which carnal and spiritual aspirations were strangely blended, the Arabs rushed forth to the field, like the war-horse of Job, “that smelleth the battle afar off, the thunder of the captains and the shouting.”  Sullen constraint was in a moment transformed into an absolute devotion and fiery resolve to spread the faith.  The Arab warrior became the missionary of Islam.