Biblical Commentary on the Old Testament, by Carl Friedrich Keil and Franz Delitzsh, [1857-78], at sacred-texts.com
The account of the siege of Rabbah, the capital, in the following year, Ch1 20:1-3, is much abridged as compared with that in Sa2 11:1; Sa2 12:26-31. After the clause, "but David sat (remained) in Jerusalem," in 2 Sam 11, from Sa2 11:2 onwards, we have the story of David's adultery with Bathsheba, and the events connected with it (2 Sam 11:3-12:25), which the author of the Chronicle has omitted, in accordance with the plan of his book. Thereafter, in Sa2 12:26, the further progress of the siege of Rabbah is again taken up with the words, "And Joab warred against Rabbah of the sons of Ammon;" and in Sa2 12:27-29 the capture of that city is circumstantially narrated, viz., how Joab, after he had taken the water-city, i.e., the city lying on both banks of the upper Jabbok (the Wady Ammn), with the exception of the Acropolis built on a hill on the north side of the city, sent messages to David, and called upon him to gather together the remainder of the people, i.e., all those capable of bearing arms who had remained in the land; and how David, having done this, took the citadel. Instead of this, we have in the Chronicle only the short statement, "And Joab smote Rabbah, and destroyed it" (Ch1 20:1, at the end). After this, both narratives (Ch1 20:2, Ch1 20:3, and Sa2 12:30, Sa2 12:31) coincide in narrating how David set the heavy golden crown of the king of the Ammonites on his head, brought much booty out of the city, caused the prisoners of war taken in Rabbah and the other fenced cities of the Ammonites to be slain in the cruellest way, and then returned with all the people, i.e., with the whole of his army, to Jerusalem. Thus we see that, according to the record in the Chronicle also, David was present at the capture of the Acropolis of Rabbah, then put on the crown of the Ammonite king, and commanded the slaughter of the prisoners; but no mention is made of his having gone to take part in the war. By the omission of this circumstance the narrative of the Chronicle becomes defective; but no reason can be given for this abridgment of the record, for the contents of Sa2 12:26-31 must have been contained in the original documents made use of by the chronicler. On the differences between Sa2 12:31 (Sam.) and Ch1 20:3 of the Chronicle, see on Sa2 12:31. ויּשׂר, "he sawed asunder," is the correct reading, and ויּשׂם in Samuel is an orthographical error; while, on the contrary, בּמּגרות in the Chronicle is a mistake for בּמגזרות in Samuel. The omission of בּמּלבּן אותם והעביר is probably explained by the desire to abridge; for if the author of the Chronicle does not scruple to tell of the sawing asunder of the prisoners with saws, and the cutting of them to pieces under threshing instruments and scythes, it would never occur to him to endeavour to soften David's harsh treatment of them by passing over in silence the burning of them in brick-kilns.
The passages parallel to the short appendix-like accounts of the valiant deeds of the Israelitish leaders in Ch1 20:4-8 are to be found, as has already been remarked, in Sa2 21:18-22. There, however, besides the three exploits of which we are informed by the chronicler in Sa2 21:15-17, a fourth is recorded, and that in the first place too, viz., the narrative of David's fight with the giant Jishbi-Benob, who was slain by Abishai the son of Zeruiah. The reason why our historian has not recounted this along with the others is clear from the position which he assigns to these short narratives in his book. In the second book of Samuel they are recounted in the last section of the history of David's reign, as palpable proofs of the divine grace of which David had had experience during his whole life, and for which he there praises the Lord in a psalm of thanksgiving (2 Sam 22). In this connection, David's deliverance by the heroic act of Abishai from the danger into which he had fallen by the fierce attack which the Philistine giant Jishbi-Benob made upon him when he was faint, is very suitably narrated, as being a visible proof of the divine grace which watched over the pious king. For the concluding remark in Sa2 21:17, that in consequence of this event his captains adjured David not to go any more into battle along with them, that the light of Israel might not be extinguished, shows in how great danger he was of being slain by this giant. For this reason the author of the book of Samuel has placed this event at the head of the exploits of the Israelite captains which he was about to relate, although it happened somewhat later in time than the three exploits which succeed. The author of the Chronicle, on the contrary, has made the account of these exploits an appendix to the account of the victorious wars by which David obtained dominion over all the neighbouring peoples, and made his name to be feared among the heathen, as a further example of the greatness of the power given to the prince chosen by the Lord to be over His people. For this purpose the story of the slaughter of the Philistine giant, who had all but slain the weary David, was less suitable, and is therefore passed over by the chronicler, although it was contained in his authority,
(Note: Lightfoot says, in his Chronol. V. T. p. 68: Illud praelium, in quo David in periculum venit et unde decore et illaesus exire non potuit, omissum est.)
as is clear from the almost verbal coincidence of the stories which follow with Sa2 21:18. The very first is introduced by the formula, "It happened after this," which in 2nd Samuel naturally connects the preceding narrative with this; while the chronicler has retained אהרי־כן as a general formula of transition, - omitting, however, עוד (Sam.) in the following clause, and writing ותּעמוד, "there arose," instead of ותּהי. עמד in the later Hebrew is the same as קוּם. The hypothesis that ותעמד has arisen out of עוד ותּהי (in Samuel) is not at all probable, although עמד is not elsewhere used of the origin of a war. Even קוּם is only once (Gen 41:30) used of the coming, or coming in, of a time. On בּגזר and ספּי instead of בּנב and סף, see on Sa2 21:18. ויּכּנעוּ at the end of the fourth verse is worthy of remark, "And they (the Philistines) were humbled," which is omitted from Samuel, and "yet can scarcely have been arbitrarily added by our historian" (Berth.). This remark, however, correct as it is, does not explain the omission of the word from 2nd Samuel. The reason for that can scarcely be other than that it did not seem necessary for the purpose which the author of the book of Samuel had in the first place in view. As to the two other exploits (Ch1 20:6-8), see the commentary on Sa2 21:19-22. אל for אלּה in the closing remark (Ch1 20:8) is archaic, but the omission of the article (אל instead of האל, as we find it in Gen 19:8, Gen 19:25, and in other passages in the Pentateuch) cannot be elsewhere paralleled. In the last clause, "And they fell by the hand of David, and by the hand of his servants," that David should be named is surprising, because none of those here mentioned as begotten of Rapha, i.e., descendants of the ancient Raphaite race, had fallen by the hand of David, but all by the hand of his servants. Bertheau therefore thinks that this clause has been copied verbatim into our passage, and also into Sa2 21:22, from the original document, where this enumeration formed the conclusion of a long section, in which the acts of David and of his heroes, in their battles with the giants in the land of the Philistines, were described. But since the author of the second book of Samuel expressly says, "These four were born to Rapha, and they fell" (Sa2 21:22), he can have referred in the words, "And they fell by the hand of David," only to the four above mentioned, whether he took the verse in question unaltered from his authority, or himself added אלּה את־ערבּעת. In the latter case he cannot have added the בּיד־דּוד without some purpose; in the former, the reference of the בּיד־דּוד in the "longer section," from which the excerpt is taken, to others than the four giants mentioned, to Goliath perhaps in addition, whom David slew, is rendered impossible by אלּה את־ערבּעת. The statement, "they fell by the hand of David," does not presuppose that David had slain all of them, or even one of them, with his own hand; for בּיד frequently signifies only through, i.e., by means of, and denotes here that those giants fell in wars which David had waged with the Philistines - that David had been the main cause of their fall, had brought about their death by his servants through the wars he waged.