A Commentary, Critical, Practical, and Explanatory on the Old and New Testaments, by Robert Jamieson, A.R. Fausset and David Brown  at sacred-texts.com
1 Chronicles 12:1
ch1 12:1THE COMPANIES THAT CAME TO DAVID AT ZIKLAG. (1Ch. 12:1-22)
Now these are they that came to David to Ziklag--There are three lists given in this chapter, arranged, apparently, according to the order of time when the parties joined the standard of David.
while he yet kept himself close because of Saul--that is, when the king's jealousy had driven him into exile from the court and the country.
Ziklag--(See on Sa1 27:6). It was during his retirement in that Philistine town that he was joined in rapid succession by the heroes who afterwards contributed so much to the glory of his reign.
1 Chronicles 12:2
ch1 12:2of Saul's brethren of Benjamin--that is, of the tribe of Benjamin (compare Ch1 12:29), but some of them might be relatives of the king. This movement to which the parties were led, doubtless by the secret impulse of the Spirit, was of vast importance to the cause of David, as it must have been founded on their observation of the evident withdrawal of God's blessing from Saul, and His favoring presence with David, to whom it was universally known the Divine King of Israel had given the crown in reversion. The accession of the Benjamites who came first and their resolution to share his fortunes must have been particularly grateful to David. It was a public and emphatic testimony by those who had enjoyed the best means of information to the unblemished excellence of his character, as well as a decided protest against the grievous wrong inflicted by causelessly outlawing a man who had rendered such eminent services to his country.
1 Chronicles 12:4
ch1 12:4Ismaiah the Gibeonite--It appears that not only the Canaanites who were admitted into the congregation (Jos. 9:1-27), but people of the tribe of Benjamin, were among the inhabitants of Gibeon. The mention of "the Gederathite," probably from Gederah (Jos 15:36), in the lowlands of Judah; of the Korhites (Ch1 12:6), from Korah (Ch1 2:43), and of Gedor (Ch1 12:7), a town in Judah, to the southwest of Beth-lehem (compare Ch1 4:4), shows that this first list contains men of Judah as well as Benjamin [BERTHEAU].
1 Chronicles 12:8
ch1 12:8of the Gadites there separated themselves unto David--that is, from the service of Saul and from the rest of the Gadites who remained steadfast adherents of his cause.
into the hold--or fortress, that is, of Ziklag, which was in the wilderness of Judah.
whose faces were like the faces of lions, &c.--A fierce, lion-like countenance (Sa2 1:23), and great agility in pursuit (Sa2 2:18), were qualities of the highest estimation in ancient warfare.
1 Chronicles 12:14
ch1 12:14one of the least was over an hundred, and the greatest over a thousand--David, while at Ziklag, had not so large an amount of forces as to give to each of these the command of so many men. Another meaning, therefore, must obviously be sought, and excluding was, which is a supplement by our translators, the import of the passage is, that one of the least could discomfit a hundred, and the greatest was worth a thousand ordinary men; a strong hyperbole to express their uncommon valor.
1 Chronicles 12:15
ch1 12:15These are they that went over Jordan in the first month--that is, in spring, when the swollen river generally fills up the banks of its channel (see on Jos 3:14; Jos 4:19; Jos 5:10).
they put to flight all them of the valleys--This was probably done at the time of their separating themselves and their purpose being discovered, they had to cut their passage through the opposing adherents of Saul, both on the eastern and western banks. The impossibility of taking the fords at such a time, and the violent rapidity of the current, make this crossing of the Jordan--in whatever way these Gadites accomplished it--a remarkable feat.
1 Chronicles 12:16
ch1 12:16the children of Benjamin and Judah--It is probable that the Benjamites invited the Judahites to accompany them, in order to prevent David being suspicious of them. Their anticipations, as the result showed, were well founded. He did suspect them, but the doubts of David as to their object in repairing to him, were promptly dispelled by Amasai or Amasa, who, by the secret impulse of the Spirit, assured him of their strong attachment and their zealous service from a unanimous conviction that his cause was owned and blessed of God (Sa1 18:12-14).
1 Chronicles 12:19
ch1 12:19there fell some of Manasseh--The period of their accession is fixed as the time when David came with the Philistines against Saul to battle.
but they helped them not--(See on Sa1 29:4).
1 Chronicles 12:20
ch1 12:20As he went to Ziklag--If those Manassites joined him on his return to Ziklag, after his dismissal from the Philistine army, then their arrival took place before the battle of Gilboa could have been fought (compare Sa1 29:11). Convinced of the desperate state of Saul's affairs, they abandoned him, and resolved to transfer their allegiance to David. But some learned men think that they came as fugitives from that disastrous field [CALMET and EWALD].
captains of the thousands . . . of Manasseh--Those seven were commanders of the large military divisions of their tribe.
1 Chronicles 12:21
ch1 12:21they helped David against the band--that is, the Amalekites who had pillaged Ziklag in David's absence. This military expedition was made by all his men (Sa1 30:9), who, as David's early helpers, are specially distinguished from those who are mentioned in the latter portion of the chapter.
1 Chronicles 12:22
ch1 12:22the host of God--that is, a great and powerful army.
1 Chronicles 12:23
ch1 12:23THE ARMIES THAT CAME TO HIM AT HEBRON. (1Ch. 12:23-40)
these are the numbers of the bands . . . that came to David to Hebron--after the death of Ish-bosheth (see on Sa2 5:1).
to turn the kingdom of Saul to him, according to the word of the Lord-- (Ch1 10:14; Ch1 11:3, Ch1 11:10). The account commences with the southern tribes, Levi being associated with Judah and Simeon, as the great majority of the leading men in this tribe resided in Judah; and, after recounting the representatives of the northern tribes, it concludes with those on the east of Jordan.
1 Chronicles 12:27
ch1 12:27Jehoiada, the leader of the Aaronites--not the high priest, for that was Abiathar (Sa1 23:9), but the leader of the Aaronite warriors, supposed to be the father of Benaiah (Ch1 11:22).
1 Chronicles 12:29
ch1 12:29Benjamin . . . three thousand--This small number shows the unpopularity of the movement in this tribe; and, indeed, it is expressly stated that the mass of the population had, even after Ish-bosheth's death, anxiously endeavored to secure the crown in the family of Saul.
1 Chronicles 12:32
ch1 12:32children of Issachar, . . . that had understanding of the times, &c.--Jewish writers say that the people of this tribe were eminent for their acquirements in astronomical and physical science; and the object of the remark was probably to show that the intelligent and learned classes were united with the military, and had declared for David.
1 Chronicles 12:33
ch1 12:33Zebulun . . . could keep rank--that is, were more disciplined soldiers than the rest.
not of double heart--Though their numbers were large, all were in a high degree well affected to David.
1 Chronicles 12:38
ch1 12:38all the rest also of Israel were of one heart to make David king--that is, entertained a unanimous desire for his elevation.
1 Chronicles 12:39
ch1 12:39there they were with David three days, eating and drinking--According to the statements made in the preceding verses, the number of armed warriors assembled in Hebron on this occasion amounted to three hundred thousand. Supplies of provisions were abundantly furnished, not only by the people of the neighborhood, but from distant parts of the country, for all wished the festivities to be on a scale of liberality and magnificence suitable to the auspicious occasion.