Albert Barnes Commentary 2 Kings 6:22

"And he answered, Thou shalt not smite them: wouldest thou smite those whom thou hast taken captive with thy sword and with thy bow? set bread and water before them, that they may eat and drink, and go to their master." — 2 Kings 6:22 (ASV)

Would you smite ... - It is doubtful whether this sentence is truly a question. Others translate it as, “Smite those whom you have taken captive with your sword,” etc. A contrast is intended between ordinary captives—those taken with the sword and bow—and these particular prisoners who have been given into the king’s hand by God. The former, Jehoram is told, he may slay if he pleases (Deuteronomy 20:13); the latter, he is informed, he must not slay (compare the marginal reference).