Charles Ellicott Commentary 1 Samuel 30:20

"And David took all the flocks and the herds, [which] they drove before those [other] cattle, and said, This is David`s spoil." — 1 Samuel 30:20 (ASV)

The flocks and the herds, which they drove. —In the English translation the word “which,” inserted in italics, obscures the sense; the literal reading is, And David took all the flocks and the herds; they drove them before their cattle, and said, this is David’s spoil. David took, no doubt, by popular acclamation as his share of the plunder, all the flocks and herds belonging to the Amalekites, mostly acquired, no doubt, in the late raid; these were driven in front of “those cattle,” thus particularizing the cattle of Ziklag belonging to David’s own people. Of course, this plunder went back to the original Israelite owners.

The drovers, as they marched behind the vast herds of Amalekite cattle, sang of the prowess of their leader in words long remembered, “See all this. This is David’s spoil.” It was “these herds”—numerically, probably very great—that David distributed among the friendly cities of the south. (See 1 Samuel 30:26, 31.) All the other plunder of the camp—arms, accoutrements, ornaments, jewels, camels’ cloths, etc.—was divided, as Bishop Hervey well suggests, among the little army. David’s motive in choosing the sheep and oxen (for his warriors certainly the least desirable part of the Amalekite possession) is evident from 1 Samuel 30:26–31. They were the most acceptable presents he could make to his friends in Judah.