26 Now Joab fought against Rabbah of the children of Ammon, and took the royal city. 27 And Joab sent messengers to David, and said, I have fought against Rabbah; yea, I have taken the city of waters. 28 Now therefore gather the rest of the people together, and encamp against the city, and take it; lest I take the city, and it be called after my name. 29 And David gathered all the people together, and went to Rabbah, and fought against it, and took it. 30 And he took the crown of their king from off his head; and the weight thereof was a talent of gold, and [in it were] precious stones; and it was set on David's head. And he brought forth the spoil of the city, exceeding much. 31 And he brought forth the people that were therein, and put them under saws, and under harrows of iron, and under axes of iron, and made them pass through the brickkiln: and thus did he unto all the cities of the children of Ammon. And David and all the people returned unto Jerusalem.
Matthew Henry's Commentary on 2 Samuel 12:26-31
Commentary on 2 Samuel 12:26-31
(Read 2 Samuel 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.