27 And Jo'ab sent messengers to David, and said, "I have fought against Rabbah; moreover, I have taken the city of waters.

Matthew Henry's Commentary on 2 Samuel 12:27

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.