This line of thinking set the stage for the acceptance of papal infallibility, the cornerstone of the papal monarchy: "The Popes became the busiest men in Europe; their interventions reached down into the lowest strata of society" (Bokenkotter 112). Two of the most powerful tools in the hands of the papacy were ex-communication and deposition.
In the Middle Ages, all knowledge of the natural and the spiritual worlds was thought to be revealed by Scripture, and no scientific discoveries had yet caused people to question the accuracy of the Bible. Christians erected shrines where they worshiped passionately the relics of saints. These physical and natural representations of divinity were believed to possess the spiritual powers of the saints themselves. Therefore, many Europeans went on pilgrimages to visit the shrines of the saints. A constant stream of pilgrims made the difficult journey from Europe to Jerusalem, the city of the Holy Sepulcher.
The nobility, as well as the common people, were infused with religious fervor. Like the Old Testament warriors, the noblemen of Europe warred constantly against the enemies of their faith. The nobles had a passion for war, and their justification for this passion was chivalry. Chivalry combined the love of battle and the love of God into a lifestyle that was both physical and spirit