Commentaries
12:26-31 To be thus severe in putting the children of Ammon to slavery was a sign that David's heart was not yet made soft by repentance, at the time when this took place. We shall be most compassionate, kind, and forgiving to others, when we most feel our need of the Lord's forgiving love, and taste the sweetness of it in our own souls.
30. he took their king's crown from off his head—While the treasures of the city were given as plunder to his soldiers, David reserved to himself the crown, which was of rarest value. Its great weight makes it probable that it was like many ancient crowns, not worn, but suspended over the head, or fixed on a canopy on the top of the throne.
the precious stones—Hebrew, "stone"; was a round ball composed of pearls and other jewels, which was in the crown, and probably taken out of it to be inserted in David's own crown.