This seems to be more than the fact deserved, or than he had commission to inflict for it, Exodus 22:1. But it is observable, that David now, when he was most indulgent to himself, and to his own sin, was most severe to others; as appears by this passage and the following relation, 2 Samuel 12:31, which was done in the time of David's impenitent continuance in his sin.
Related Commentaries of 2 Samuel 12:5
2 Samuel 12:5
5 And David's anger was greatly kindled against the man; and he said to Nathan, As the LORD liveth, the man that hath done this thing shall surely die: