Two causes are indicated in the text. One is, the oath given her by the spies (v. 22). The other is, because she had hidden those very spies, and was [thus] safe (vv. 17 and 25). From the former a distinguished example is drawn, that we may understand how great ought to be our religious regard for an oath. Certainly, says Masius, “a most upright Commander recalls to them
(col. 807)
their oath to their memory. For although in that which they [the spies] had given privately, they had not bound the Commander [Joshua] or the army: yet, since they at least were held bound by the sacred bond, the religious scruple of that best Commander was solicitous even for the pledged faith of two of his common soldiers. But if the leaders of our age, and the commanders of armies, would set such examples before themselves to imitate, surely less deadly wars would be waged — which now the rest wage after every appearance of the savagery of all barbarians, sparing themselves in nothing, not only against enemies, but (what is most unworthy) against allies and friends.” See Seneca, book four On Benefits, chs. 25, 26. From the latter [cause] we are taught how deeply received benefits ought to be fixed in our minds, and, when it is lawful and fitting, recompensed. Two Israelites were guarded and preserved by Rahab: but now not two only, but by the Israelites very many of Rahab’s people are guarded and preserved. Rahab bestowed one benefit only: now that benefit is repaid both by those same two Israelites who received it, and, for their sake, by the whole army, and by the Commander. The life of two was covertly and skillfully protected: now the safety of Rahab herself, and of [her] father, and mother, and brothers, and of all [her] kinsfolk and household is defended and preserved publicly and openly, in the utmost peril of all the others, and in [their] final destruction. So benefits are to be returned — not equal for equal, but, since you can, even by the least, in due time and place, to be repaid. One thing is justice, which is called commutative; and another is gratitude: gratitude does not call these [benefits] back to niggling reckonings because it received [them]. Where occasion and power is, it pours itself wholly out: for a cup of water, gallons of wine; for a morsel, measures of grain; for an ounce, the whole As [coin] — and whatever there is beyond that? — it gladly gives. Rahab covered the spies: by those same [men] she is now made illustrious; she is set, in the eyes and speech of all, with great praise; under the flax those [spies] were hidden by her; by them she is now borne and celebrated above the roofs of this whole world; through the window and the cords they were let down by her secretly; by them she is now led out through the open gates of the city, by most friendly hands, away from slaughter and flames. But if reason bids us [be] so grateful in bodily benefits, what is to be done in those which regard, and preserve, and adorn the soul? But see the same [author, Seneca] in those same most beautiful books, and Valerius Maximus (bk. 5, ch. 2), where he relates how, when Capua was taken, freedom was given to Cluvia, a servant-harlot, because she had furnished provisions to the Roman soldiers.