I know it is quite long, but I can't understand what it is exactly saying.
God allowed the Western church, on account of its sins, to be cast down. There arose, indeed, certain pseudo prophets, sons of Belial, and witnesses of anti-Christ, who seduced the Christians with empty words. They constrained all sorts of men, by vain preaching, to set out against the Saracens in order to liberate Jerusalem. The preaching of these men was so enormously influential that the inhabitants of nearly every region, by common vows, offered themselves freely for common destruction. Not only the ordinary people, but kings, dukes, marquises, and other powerful men of this world as well, believed that they thus showed their allegiance to God. The bishops, archbishops, abbots, and other ministers and prelates of the church joined in this error, throwing themselves headlong into it to the great peril of bodies and souls… The intentions of the various men were different. Some, indeed, lusted after novelties and went in order to learn about new lands. Others there were who were driven by poverty, who were in hard straits at home; these men went to fight, not only against the enemies of Christ's cross, but even against the friends of the Christian name, wherever opportunity appeared, in order to relieve their poverty. There were others who were oppressed by debts to other men or who sought to escape the service due to their lords, or who were even awaiting the punishment merited by their shameful deeds. Such men simulated a zeal for God and hastened chiefly in order to escape from such troubles and anxieties. A few could, with difficulty, be found who had not bowed their knees to Baal, who were directed by a holy and wholesome purpose, and who were kindled by love of the divine majesty to fight earnestly and even to shed their blood for the holy of holies
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