The Lord hath spoken By the hand of my servant David, &c. We nowhere find these words recorded; but it is probable Samuel had often spoken them; at least the sense of them is implied in the words of God to Samuel, when he commanded him to anoint David king over Israel, 1 Samuel 10:1-12; for the intention of giving them a king was, that he might fight their battles, 1 Samuel 8:20.
Related Commentaries of 2 Samuel 3:18
2 Samuel 3:18
18 Now then do it: for the LORD hath spoken of David, saying, By the hand of my servant David I will save my people Israel out of the hand of the Philistines, and out of the hand of all their enemies.