Notes on the Bible, by Albert Barnes, [1834], at sacred-texts.com
There is no note of time whatever, nor any clue as to what part of David's reign the events of this chapter ought to be assigned.
Enquired of the Lord - Hebrew "sought the face of the Lord," quite a different phrase from that so often used in Judges (e. g. Jdg 1:1) and the Books of Samuel, and probably indicating that this chapter is from a different source; an inference agreeing with the indefinite "in the days of David," and with the allusion to the slaughter of the Gibeonites, which has not anywhere been narrated.
And for his bloody house - literally, "the house of blood," i. e., the house or family upon which rests the guilt of shedding innocent blood.
The way in which the writer here refers to the history of the league with the Gibeonites Josh. 9 shows that the Book of Joshua was not a part of the same work as the Books of Samuel.
Of the Amorites - The Gibeonites were Hivites Jos 9:7; Jos 11:19; and in many enumerations of the Canaanite nations the Hivites are distinguished from the Amorites. But "Amorite" is often used in a more comprehensive sense, equivalent to "Canaanite" (as Gen 15:16; Deu 1:27), and denoting especially that part of the Canaanite nation which dwelt in the hill country Num 13:29; Deu 1:7, Deu 1:20, Deu 1:24, and so includes the Hivites.
No silver, nor gold ... - Money payments as a compensation for blood-guilt were very common among many nations. The law, too, in Num 35:31-32, presupposes the existence of the custom which it prohibits. In like manner the speech of the Gibeonites implies that such a payment as they refuse would be a not unusual proceeding.
Neither ... shalt thou kill any man in Israel - They mean that it is not against the nation of Israel, but against the individual Saul, that they cry for vengeance. The demand for Saul's sons is exactly similar to that which dictated David's own expression in Sa2 24:17, "against me, and against my father's house."
Seven men - Seven was a sacred number not only with the Hebrews but with other Oriental nations Num 23:1, Num 23:29, and is therefore brought in on this occasion when the judicial death of the sons of Saul was a religious act intended to appease the wrath of God for the violation of an oath Num 25:4.
Whom the Lord did choose - Rather, "the Lord's chosen," or elect. The same phrase is applied to Moses Psa 106:23, to the Israelites Isa 43:20, and to Christ Isa 42:1.
The Lord's oath - The calamity brought upon Israel by Saul's breach of the oath to the Gibeonites would make David doubly careful in the matter of his own oath to Jonathan.
Rizpah - See the marginal reference. A foreign origin was possibly the cause of the selection of Rizpah's sons as victims.
Sons of Michal - An obvious error for "Merab" (Sa1 18:19 note).
In the first days - The barley harvest (about the middle or toward the end of April) was earlier than the wheat harvest Exo 9:31; Rut 1:22.
Dropped - Rather, "poured," the proper word for heavy rain Exo 9:33. The "early rain," or heavy rain of autumn, usually began in October, so that Rizpah's devoted watch continued about six months. How rare rain was in harvest we learn from Sa1 12:17-18; Pro 26:1. The reason of the bodies being left unburied, contrary to Deu 21:23, probably was that the death of these men being an expiation of the guilt of a violated oath, they were to remain until the fall of rain should give the assurance that God's anger was appeased, and the national sin forgiven.
Birds of the air ... beasts of the field - It is well known how in the East, on the death e. g. of a camel in a caravan, the vultures instantly flock to the carcass. (Compare Mat 24:28.)
From the street of Beth-shan - This was the wide place just inside the gate of an Oriental city, bounded therefore by the city wall (compare the marginal reference). Here, as the place of concourse, the Philistines had fastened the bodies.
This, like the preceding paragraph Sa2 21:1-14, is manifestly a detached and unconnected extract. It is probably taken from some history of David's wars, apparently the same as furnished the materials for 2 Sam. 5; 8; 23:8-39. There is no direct clue to the time when the events here related took place, but it was probably quite in the early part of David's reign, while he was still young and active, after the war described in 2 Sam. 5. The Book of Chronicles places these Philistine battles immediately after the taking of Rabbah of the Ammonites Ch1 20:4-8, but omits David's adventure Sa2 21:15-17.
Ishbi-benob - A corrupt reading. The whole passage should perhaps run thus: "And David waxed faint. So they halted in Gob (as in Sa2 21:18-19). And there was a man (in Gob) which was of the sons of the giant, etc."
Sons of the giant - The "giant" here Sa2 21:18, Sa2 21:20, Sa2 21:22 is "ha-Raphah," whence, the "Rephaim" Gen 14:5; Deu 2:11. The sons of Ha-raphah, or Rephaim, are different from the "Nephilim," or Giants Gen 6:4; Num 13:33. The sons of Anak were not strictly Rephaim, but Nephilim.
Three hundred shekels of brass - About eight pounds. Goliath's spear's head weighed "six hundred shekels of iron."
A battle in Gob - In the parallel passage (marginal reference), "Gezer" is named as the field of this battle. However, Gath is named Sa2 21:20, Sa2 21:22 in a way to make it probable that Gath was the scene of all the battles. The Septuagint in this verse has "Gath."
The Hebrew text is manifestly very corrupt. First, for "Jaare-oregim," Ch1 20:5 gives us the reading Jair. "Oregim" has evidently got in by a transcriber's error from the line below, where "oregim" is the Hebrew for "weavers." Again, the word the "Bethlehemite" is very doubtful. It is supported by Sa2 23:24, but it is not found in the far purer text of Ch1 20:5, but instead of it we find the name of the Philistine slain by Elhanan, "Lahmi the brother of Goliath the Gittite." It is probable, therefore, that either the words "the Bethlehemite," are a corruption of "Lahmi," or that the recurrence of "Lahmi," and the termination of "Beth-lehemite" has confused the transcriber, and led to the omission of one of the words in each text.
Four - Not necessarily meaning that they were brothers, but that they were all of the race of the Giant, all Rephaim. The word "four" is omitted in the parallel passage, only the three last being mentioned in that chapter.