This is a compilation of passages from pre-Nicene Christian literature about the Just War tradition, along with a couple of summaries regarding the Thundering Legion and the Theban Legion, two early military companies that some Catholic soldiers belonged to. I wanted to make this compilation because I often see non-Catholics arguing that the early Church changed its doctrine on this point, and I think that’s bogus. You can use this resource in discussing the unchangeability of Church doctrine when that subject comes up.
By the way, two things: first, I stop at the Nicene Council because everybody knows that there were tons of faithful Catholic soldiers and military supporters after Constantine became emperor. Second, I’m sure there are other, similar examples where other early Catholics wrote about fighting in a war justly, or did so. Anybody care to post some?
The Just War Tradition in the Doctrine of the Pre-Nicene Church
~56 A.D. - St. Paul - “[The government] is God’s servant for your good. But if you do wrong, be afraid, for he does not bear the sword in vain; he is the servant of God to execute his wrath on the wrongdoer.” (Romans 13:4)
~160 A.D. - The Thundering Legion was a military company which Catholic soldiers are known to have belonged to before Constantine became emperor. The Emperor Marcus Aurelius remarked that at least some of the Catholic soldiers had conscientious objections to bearing arms, but the soldiers were not pacifists because they prayed for God to help the Roman combatants and defeat their opponents: “[T]hey began the battle, not by preparing weapons, nor arms, nor bugles; for such preparation is hateful to them, on account of the God they bear about in their conscience…[but] they prayed not only for me, but also for the whole army…[and] upon the enemies of Rome [God poured] a withering hail.” (Marcus Aurelius, Letter to the Senate on the campaign in Germany)
180 A.D. - St. Irenaeus - “[The] virtue[s], [which] are laborious, glorious, and skilful, which also are approved universally as being good…[include those] connected with a maritime life, gymnastic exercises, hunting, military and kingly pursuits.” (Against Heresies Book II Chapter 32 Paragraph 2)
195 A.D. - St. Clement of Alexandria - “[For Moses] there was just cause of hostilities [against the Egyptians]. The Hebrews came as suppliants to the Egyptians on account of famine; and they, reducing their guests to slavery, compelled them to serve them after the manner of captives, giving them no recompense.” “[Therefore,] as may be alleged is done in war, [the Israelites] thought it proper [to] exercise…the rights of conquerors…[against] their enemies, as those who have gained the day do from those who are worsted.” (Stromata Book 1 Chapter 23)
And: “Tactics belong to military command, and the ability to command an army is among the attributes of kingly rule. … Of the kingly office one kind is divine—that which is according to God and His holy Son… And there is a second kind…[the human,] which brings to the task of government merely the high mettle of the soul; after which fashion Hercules ruled the Argives, and Alexander the Macedonians. The third kind is what aims after one thing—merely to conquer and overturn… [This attitude] is solely the result of passion, and acquires power solely for the sake of domination; while, on the other, the love of good is characteristic of a soul which uses its high spirit for noble ends.” (Stromata Book 1 Chapter 24)
And: “Sail the sea, you who are devoted to navigation, yet call the while on the heavenly Pilot. Has [saving] knowledge taken hold of you while engaged in military service? Listen to the commander, who orders what is right.” (Exhortation to the Heathen Chapter 10)
197 A.D. - Tertullian - “We pray for…security to the empire; for protection to the imperial house; for brave armies, a faithful senate, a virtuous people, the world at rest, whatever, as man or Cæsar, an emperor would wish.” (Apology Chapter 30)
And: “We sail with you and fight with you, and till the ground with you; and in like manner we unite with you in your traffickings.” (Apology Chapter 42)
248 A.D. - Origen - “[W]hile others are engaged in battle, [Christians] engage as the priests and ministers of God, keeping their hands pure, and wrestling in prayers to God on behalf of those who are fighting in a righteous cause, and for the king who reigns righteously, that whatever is opposed to those who act righteously may be destroyed!” (Contra Celsus Book 8 Chapter 73)
286 A.D. - The Theban Legion was another military company which Catholic soldiers are known to have belonged to before Constantine became emperor. The whole company was martyred during the persecution by Emperor Diocletian, after whose death Constantine gained the throne.
314 A.D. - Council of Arles - “Those who throw down their arms in time of peace are to be separated from the [Church].” (Canon 3)
319 A.D. - Eusebius - “[The way of life] permits men to join in pure nuptials and to produce children, to undertake government, to give orders to soldiers fighting for right; it allows them to have minds for farming, for trade, and the other more secular interests as well as for religion…[for] all men, whether Greeks or barbarians, have their part in the coming of salvation, and profit by the teaching of the Gospel.” (Proof of the Gospel Book I Chapter 8)
~320 A.D. - St. Lactantius - “[The passions] are not evil of themselves, since God has reasonably implanted them in us; but inasmuch as they are plainly good by nature—for they are given us for the protection of life—they become evil by their evil use. And as bravery, if you fight in defence of your country, is a good, if against your country, is an evil, so the passions, if you employ them to good purposes, will be virtues, if to evil uses, they will be called vices.” (Epitome of the Divine Institutes Chapter 61)