In taming the barbarians, the Church funneled their combativeness to the service of Christendom, giving rise to Chivalry and the Crusades
nobility.org
Providence disposed that the Middle Ages should be a specially warlike age. This was not only because of the double effort that Charlemagne had to do by fighting both Saracens and barbarians, but also because of the remaining traits of barbarian mentality in Catholics themselves, which led them to unsheathe their swords and combat for trivial motives, or for no reason at all.
This caused the Church to gradually tighten the screws and limit all that by taming people’s customs, etc. in order to curb that [warlike] mentality but, in curbing it, to also channel and elevate it to good things. Whenever the Church finds herself before something in the soul of her faithful which is exaggerated, though not bad as such and which can even be tweaked toward the good, She tries to restrain the exaggeration and at the same time channel the good thing to its higher aspects. This She did magnificently, also with the Crusading spirit. And from that came chivalry, the Crusades and everything we know.
… Specifically, it was a twofold offensive against Christendom. The Church had to defend Herself, and She did so by stimulating this spirit within Her ranks. And from this came the encouragement provided for, and the sanctification of the Crusades.
(Excerpt from an AlmoƧo Tuesday, Jan. 30, 1990 – Nobility.org)
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