Question XII. Since the Israelites were not bound by that oath, [did they] rightly keep it?

To some [it] seems [that] this oath was not rightly kept. First: Because in the Council of Elvira [Elibertinum] (ch. 1), and in Gratian (causa 22, q. 4), it is said: “A rash determination is laudably to be dissolved: nor is it a prevarication, but a correction of the rashness.” And Bede (on the feast of the Beheading of St. John): “Foolish vows,” he says, “are to be broken.” More [things] to the same effect are adduced [in] the same causa 22 (chapters “si aliquid,” “Actione quarta,” “si quis praeventus,” “Mulier”). Secondly: Because the whole assembly of the Israelites disapproved the keeping of this oath, and murmured against the Princes. Thirdly: The obligation of the oath ceasing, the former condition of the Israelites returned. But that was of such a kind, that they had to bring utter destruction and ruin upon all the Canaanites (Deut. 20, v. 16). Fourthly: Cicero (bk. 1, On Duties): “Who does not see that those promises are not to be kept, which one had promised compelled by fear, or deceived by guile?” — To others [it] seems [that] the oath was rightly kept, in a threefold [manner]. First: Because God had either revealed or inspired [that] it must be done thus. So partly Abulensis, partly others [cited] in him (qq. 30, 31, 32). Secondly: Because the princes thought themselves bound by it. Although indeed [one] is not [truly] bound, yet they could by no means act against their own conscience, because “everything which is not of faith is sin” (Rom. 14, last verse). Thirdly: Because, although they knew indeed [that] they were not bound by it, yet — to show how greatly the sacredness of an oath is to be esteemed — they wished to keep it, and rightly kept [it]. And this pleases me exceedingly. For, first, no law forbade Canaanites who bid farewell to the vain superstitions of idols to be preserved safe and unharmed, as I said above (q. 8). Secondly, so great an ignorance of law seems scarcely to fall upon so great a Senate, and so great a Prince — and the same, so great a Prophet, Joshua — and upon the High Priest Eleazar too, whom Josephus [is] witness to have been present at all these [affairs]. Thirdly: No revelation is read of; [but] inspiration in benefactions of this kind is rightly granted. Fourthly: The Lord approved the judgment about this rightly-observed oath, both then, and many years after — as is clear from [what is] no less than 2 Kings [2 Samuel] 21. Fifthly: In this way a greater occasion was given to the Canaanites of converting themselves to the true God; and a greater reproach of most just punishment [was given] to the stubborn, and [those] contumacious in idolatry. Sixthly: So also St. Ambrose thinks (bk. 1, On Duties, ch. 29; bk. 3, ch. 10), whose words will be cited later. Seventhly: To be tenacious of promises and oaths, even with some inconvenience to oneself, has greater force for moving the minds of others to sacred fidelity, than if what was incautiously promised or sworn should at once be rescinded. Whence also St. Bernard (Epistle 219): “It is reckoned a disgrace among the Franks to loose an oath, however ill it was publicly sworn.” Eighthly: This constancy of the Israelites in [their] agreements and pacts is praised in the chapter “Venerabilem” (in the Extra[vagantes], On Election): “Since the Gabaonites had filched an oath from the sons of Israel by fraud, yet they [the Israelites], the fraud being known, would not rashly go against it.”