“What is the evil of war? Is it the death of some who will soon die in any case, that others may live in peaceful subjection? This is merely cowardly dislike, not any religious feeling. The real evils in war are love of violence, revengeful cruelty, fierce and implacable enmity, wild resistance, and the lust of power, and such like; and it is generally to punish these things, when force is required to inflict the punishment, that, in obedience to God or some lawful authorities, good men undertake wars, when they find themselves in such a position as regards the conduct of human affairs, that right conduct requires them to act, or to make others act, in this way.” Augustine of Hippo, Reply to Faustus the Manichaean XXII. 74. Nicene and Post-Nicene Fathers, vol. 4, p. 301.
Augustine defended the proper use of force under certain circumstances. This classic text laid the foundation for the later Christian understanding of just war. Augustine recognized the basic fact that sometimes force must be used to stop the evils of human violence. Later in this text Augustine wrote:
“A great deal depends on the causes for which men undertake wars, and on the authority they have for doing so; for the natural order which seeks the peace of mankind, ordains that the monarch should have the power of undertaking war if he thinks it advisable, and that the soldiers should perform their military duties in behalf of the peace and safety of the community. When war is undertaken in obedience to God, who would rebuke, or humble, or crush the pride of man, it must be allowed to be righteous war; for even the wars which arise from human passion cannot harm the eternal well-being of God, nor even the saints.” Augustine, Reply to Faustus the Manichaean XXII. 75. NPNF 4, p. 301.