Commentaries:
Jamieson, Fausset, and Brown
He was with David at Pas-dammim—It was at the time when he was a fugitive in the wilderness, and, parched with thirst under the burning heat of noonday, he wistfully thought of the cool fountain of his native village [II Samuel 23:15; I Chronicles 11:17]. This is a notice of the achievement, to which Eleazar owed his fame, but the details are found only in II Samuel 23:9-11, where it is further said that he was aided by the valor of Shammah, a fact corroborated in the passage before us (I Chronicles 11:14), where it is recorded of the heroes, that "they set themselves in the midst of that parcel." As the singular number is used in speaking of Shammah (II Samuel 23:12), the true view seems to be that when Eleazar had given up from exhaustion, Shammah succeeded, and by his fresh and extraordinary prowess preserved the field. 
 barley—or lentils (II Samuel 23:11). Ephes-dammim was situated between Shocoh and Azekah, in the west of the Judahite territory. These feats were performed when David acted as Saul's general against the Philistines.
Jashobeam, an Hachmonite—or, "son of Hachmoni." He is called also son of Zabdiel (I Chronicles 27:2), so that, strictly speaking, he was the grandson of Hachmoni (compare I Chronicles 27:32). 
 lifted up his spear against three hundred slain by him at one time—The feat is said (II Samuel 23:8) to have been a slaughter of eight hundred in one day. Some endeavor to reconcile the statements in that passage and in this by supposing that he slew eight hundred on one occasion and three hundred on another; while others conjecture that he attacked a body of eight hundred, and, having slain three hundred of them, the rest fled [LIGHTFOOT].
Other Jamieson, Fausset, and Brown entries containing 1 Chronicles 11:13:
1 Samuel 17:1
1 Chronicles 11:15-19
 
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