One of the problems with the debate between pacifism and just war theory is that it often strays into a theoretical argument totally untethered from the biblical texts (Camassia’s complaint), or it gets mired in pulling out various bits of Scripture and using them as proof-texts.
Proponents of Just War Theory often appeal to John the Baptist’s exhortation to the soldiers in Luke 3:
Then some soldiers asked him, “And what should we do?”
He replied, “Don’t extort money and don’t accuse people falsely–be content with your pay.” (Luke 3:14)
From this it is sometimes inferred that John must have approved of the soldiers’ occupation, and, therefore, that a Christian can licitly be a soldier and engage in war-making. If John was a pacifist he would’ve told the soldiers to give up soldiering!
St. Thomas quotes St. Augustine to this effect in his article on whether war can be just:
Objection 1. It would seem that it is always sinful to wage war. Because punishment is not inflicted except for sin. Now those who wage war are threatened by Our Lord with punishment, according to Mt. 26:52: “All that take the sword shall perish with the sword.” Therefore all wars are unlawful. […]
On the contrary, Augustine says in a sermon on the son of the centurion [Ep. ad Marcel. cxxxviii]: “If the Christian Religion forbade war altogether, those who sought salutary advice in the Gospel would rather have been counselled to cast aside their arms, and to give up soldiering altogether. On the contrary, they were told: ‘Do violence to no man . . . and be content with your pay’ [Lk. 3:14. If he commanded them to be content with their pay, he did not forbid soldiering.” (ST, Part II, Q 40)*
G.E.M. Anscombe makes a similar appeal:
To extract a pacifist doctrine–i.e., a condemnation of the use of force by the ruling authorities, and of soldiering as a profession–from the evangelical counsels and the rebuke to Peter, is to disregard what else is in the New Testament. It is to forget St. John’s direction to soldiers: “do not blackmail people; be content with your pay”; and Christ’s commendation of the centurion, who compared his authority over his men to Christ’s. On a pacifist view, this must be much as if a madam in a brothel had said: “I know what authority is, I tell this girl to do this and she does it…” and Christ had commender her faith. A centurion was the first Gentile to be baptized; there is no suggestion in the New Testament that soldiering was regarded as incompatible with Christianity. The martyrology contains many names of soldiers whose occasion of martyrdom was not any objection to soldiering, but a refusal to perform idolatrous acts.
These seem like thin reeds on which to hang a doctrine of just war. First of all, many soldiers in the Roman army were not engaged in fighting, but were little more than bureaucrats administering the vast machinery of empire. So, it seems to read a lot into the Baptist’s comments to say that he was commending war as such. This is reinforced by his admonition not to falsely accuse people – it suggests that these soldiers were acting more like military police.
Secondly, we have to reckon with Jesus’ own statements on the matter, and certainly they carry more weight than those of St. John.
But more fundamentally, it seems to me that we need a kind of overarching hermeneutic for how we extract moral norms from the New Testament. That is, a rule of interpretation for deciding which pronouncements carry the most weight, how to deal with inconsistencies (real or apparent), etc.
To make an analogy, it is often said that debates about homosexuality pit those who adhere to the “authority of the Bible” against those who don’t. A more charitable way of putting it, I think, is to say that the two sides emphasize different aspects of the Biblical witness. Those who oppose the acceptance of homosexual behavior point to Paul’s statements in Romans and elsewhere that seem to condemn same-sex relations and appeal to the creation account to argue that marriage between a man and a woman expresses the will of God. But those who argue for acceptance point to the inclusion of the Gentiles as a kind of moral precedent for not letting what they regard as outmoded “purity” regulations be the norm in the church (I realize I am not presenting these positions in all their sophistication; this is for illustrative purposes only).
The upshot is that, whatever position we take, it should be informed by a coherent account of how the Bible should function as a guide our moral life, not just by adducing texts plucked out to support a predetermined position.
*To avoid misunderstanding I should point out that Aquinas offers much more in the way of an argument than just this one text. He goes on to say:
In order for a war to be just, three things are necessary. First, the authority of the sovereign by whose command the war is to be waged. For it is not the business of a private individual to declare war, because he can seek for redress of his rights from the tribunal of his superior. Moreover it is not the business of a private individual to summon together the people, which has to be done in wartime. And as the care of the common weal is committed to those who are in authority, it is their business to watch over the common weal of the city, kingdom or province subject to them. And just as it is lawful for them to have recourse to the sword in defending that common weal against internal disturbances, when they punish evil-doers, according to the words of the Apostle (Rm. 13:4): “He beareth not the sword in vain: for he is God’s minister, an avenger to execute wrath upon him that doth evil”; so too, it is their business to have recourse to the sword of war in defending the common weal against external enemies. Hence it is said to those who are in authority (Ps. 81:4): “Rescue the poor: and deliver the needy out of the hand of the sinner”; and for this reason Augustine says (Contra Faust. xxii, 75): “The natural order conducive to peace among mortals demands that the power to declare and counsel war should be in the hands of those who hold the supreme authority.”
Secondly, a just cause is required, namely that those who are attacked, should be attacked because they deserve it on account of some fault. Wherefore Augustine says (QQ. in Hept., qu. x, super Jos.): “A just war is wont to be described as one that avenges wrongs, when a nation or state has to be punished, for refusing to make amends for the wrongs inflicted by its subjects, or to restore what it has seized unjustly.”
Thirdly, it is necessary that the belligerents should have a rightful intention, so that they intend the advancement of good, or the avoidance of evil. Hence Augustine says (De Verb. Dom. [The words quoted are to be found not in St. Augustine’s works, but Can. Apud. Caus. xxiii, qu. 1): “True religion looks upon as peaceful those wars that are waged not for motives of aggrandizement, or cruelty, but with the object of securing peace, of punishing evil-doers, and of uplifting the good.” For it may happen that the war is declared by the legitimate authority, and for a just cause, and yet be rendered unlawful through a wicked intention. Hence Augustine says (Contra Faust. xxii, 74): “The passion for inflicting harm, the cruel thirst for vengeance, an unpacific and relentless spirit, the fever of revolt, the lust of power, and such like things, all these are rightly condemned in war.”