31 And he took the people out of the town and put them to work with wood-cutting instruments, and iron grain-crushers, and iron axes, and at brick-making: this he did to all the towns of the children of Ammon. Then David and all the people went back to Jerusalem.
Matthew Henry's Commentary on 2 Samuel 12:31
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.