And he took the crown of their king from his head. The weight of it was a talent of gold, and in it was a precious stone, and it was placed on David’s head. And he brought out the spoil of the city, a very great amount.
We have here an account of the conquest of Rabbah, and other cities of the Ammonites. Though this comes in here after the birth of David's child, yet it is most probable that it was effected a good while before, and soon after the death of Uriah, perhaps during the days of Bath-sheba's mourning for him. Observe, 1.
Commenting on 2 Samuel 12:26-31
And he brought forth the people that were therein,.... Not all the inhabitants of the place, but the princes of the children of Ammon, the counsellors of Hattun, who advised him to use David's ambassadors in so shameful a manner, and others that expressed their pleasure and satisfaction in it: and put them under saws, and under harrows of iron, and under axes of iron...
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.