The Geneva Bible Translation Notes, [1599], at sacred-texts.com
(a) To take his part against Saul: who persecuted him.
[They were] armed with bows, and could use both the right hand and the left in [hurling] stones and [shooting] arrows out of a bow, [even] of Saul's (b) brethren of Benjamin.
(b) That is, of the tribe of Benjamin, of which Saul was, and in which were excellent throwers with slings, (Jdg 20:16).
And of the Gadites there separated themselves unto David into the hold to the wilderness men of might, [and] men of war [fit] for the battle, that could handle shield and buckler, whose faces [were like] the faces of (c) lions, and [were] as swift as the roes upon the mountains;
(c) Meaning, fierce and terrible.
These [are] they that went over Jordan in the (d) first month, when it had overflown all his banks; and they put to flight all [them] of the valleys, [both] toward the east, and toward the west.
(d) Which the Hebrews called Nisan, or Abib, containing half March and half April, when Jordan was wont to overflow its banks, read (Jos 3:15).
Then the (e) spirit came upon Amasai, [who was] chief of the captains, [and he said], Thine [are we], David, and on thy side, thou son of Jesse: peace, peace [be] unto thee, and peace [be] to thine helpers; for thy God helpeth thee. Then David received them, and made them captains of the band.
(e) The spirit of boldness and courage moved him to speak thus.
And there fell [some] of Manasseh to David, when he came with the Philistines against Saul to battle: but they (f) helped them not: for the lords of the Philistines upon advisement sent him away, saying, He will fall to his master Saul to [the jeopardy of] our heads.
(f) They came only to help David, and not to help the Philistines, who were enemies of their country.
And they helped David against the (g) band [of the rovers]: for they [were] all mighty men of valour, and were captains in the host.
(g) That is, of the Amalekites who had burned the city of Ziklag, (Sa1 30:1, Sa1 30:9).
For at [that] time day by day there came to David to help him, until [it was] a great host, like the host of (h) God.
(h) Meaning, mighty or strong, for the Hebrews say a thing is of God when it is excellent.
And Jehoiada [was] the leader of the (i) Aaronites, and with him [were] three thousand and seven hundred;
(i) Of the Levites who came by the descent of Aaron.
And of the children of Benjamin, the kindred of Saul, three thousand: for hitherto the greatest part of them had (k) kept the ward of the house of Saul.
(k) That is, the greatest number took Saul's side.
And of the children of Issachar, [which were men] that had understanding of the (l) times, to know what Israel ought to do; the heads of them [were] two hundred; and all their brethren [were] at their commandment.
(l) Men of good experience, who knew at all times what was to be done.
(m) All these men of war, that could keep rank, came with a perfect heart to Hebron, to make David king over all Israel: and all the rest also of Israel [were] of one heart to make David king.
(m) So that his whole host were 322,222.
And there they were with David three days, eating and drinking: for their (n) brethren had prepared for them.
(n) The rest of the Israelites.