C. F. Keil and Franz Delitzsch on 2 Kings 19:35

2Ki 19:35 The fulfilment of the divine promise. - 2Ki 19:35. “It came to pass in that night, that the angel of the Lord went out and smote in the army of the Assyrian 185,000 men; and when they (those that were left, including the king) rose up in the morning, behold there were they all (i.e., all who had perished) dead corpses,” i.e., they had died in their sleep. מתים is added to strengthen פּגרים: lifeless corpses. ההוּא בּלּילה is in all probability the night following the day on which Isaiah had foretold to Hezekiah the deliverance of Jerusalem. Where the Assyrian army was posted at the time when this terrible stroke fell upon it is not stated, since the account is restricted to the principal fact. One portion of it was probably still before Jerusalem; the remainder were either in front of Libnah (2Ki 19:8), or marching against Jerusalem. From the fact that Sennacherib’s second embassy (2Ki 19:9.) was not accompanied by a body of troops, it by no means follows that the large army which had come with the first embassy (2Ki 18:17) had withdrawn again, or had even removed to Libnah on the return of Rabshakeh to his king (2Ki 19:8). The very opposite may be inferred with much greater justice from 2Ki 19:32. And the smiting of 185,000 men by an angel of the Lord by no means presupposes that the whole of Sennacherib’s army was concentrated at one spot. The blow could certainly fall upon the Assyrians wherever they were standing or were encamped. The “angel of the Lord” is the same angel that smote as המּשׁחית the first-born of Egypt (Exo 12:23, compared with Exo 12:12 and Exo 12:13), and inflicted the pestilence upon Israel after the numbering of the people by David (2Sa 24:15-16). The last passage renders the conjecture a very probable one, that the slaying of the Assyrians was also effected by a terrible pestilence. But the number of the persons slain - 185,000 in a single night - so immensely surpasses the effects even of the most terrible plagues, that this fact cannot be interpreted naturally; and the deniers of miracle have therefore felt obliged to do violence to the text, and to pronounce either the statement that it was “the same night” or the number of the slain a mythical exaggeration.The assertion of Thenius, that 2Ki 19:35-37 are borrowed from a different source from 2Ki 18:13-19, 2Ki 18:34 and 20:1-19, rests upon purely arbitrary suppositions and groundless assumptions, and is only made in the interest of the mythical interpretation of the miracle. And his conclusion, that “since the catastrophe was evidently (?) occasioned by the sudden breaking out of a pestilence, the scene of it was no doubt the pestilential Egypt,” is just as unfounded, - as if Egypt were the only land in which a pestilence could suddenly have broken out. - The account given by Herodotus (ii. 141), that on the prayer of king Sethon, a priest of Vulcan, the deity promised him victory over the great advancing army of Sennacherib, and that during the night mice spread among the enemy (i.e., in the Assyrian camp at Pelusium), and ate up the quivers and bows, and the leather straps of the shields, so that the next morning they were obliged to flee without their weapons, and many were cut down, is imply a legendary imitation of our account, i.e., an Egyptian variation of the defeat of Sennacherib in Judah. The eating up of the Assyrian weapons by mice is merely the explanation given to Herodotus by the Egyptian priests of the hieroglyphical legend on the standing figure of Sethos at Memphis, from which we cannot even gather the historical fact that Sennacherib really advanced as far as Pelusium.