In Augustine’s theory, three kinds of war were morally defensible: a defensive war against aggression, a war to gain just reparations for previous wrong, and a war to recover stolen property.(1) There may be biblical foundations for Augustine’s deciding only to accept these three kinds of wars, or to accept any war at all, but none are given by the many sources I’ve read on the subject.  Instead, what I’ve found most often given in Augustine’s defense, as his rationale, is his seeking a practical logical compromise between rejecting all wars as evil and accepting all wars as virtuous.

“By limiting war to these categories the great theologian and bishop believed he had been faithful to both his religious doctrines and his civic duty.”(2)

Augustine adapted church doctrine on war, largely accepted but not without it’s detractors, and made it easier for Rome to swallow – whether this was his intention or not.  Christians fearing for their lives and the Emperor fearing for his empire were now given permission by God’s representative to wage three kinds of war.  This change in doctrine had momentous repercussions, for the Catholic Church was soon the dominant institution in the West, posing less threat to principalities fond of the sword.

“In midieval Europe the writings of Augustine acquired a status next to the Bible and became the chief authority in matters of faith and ethics…And so, for hundreds of years the writings of Augustine provided Western civilization with its notion of the morality of war.  The chief feature of this understanding was that at times a nation had a right, indeed a duty, to go to war.”(2)

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