Adam Clarke's Commentary on the Bible

Verse 5 (2 Samuel 19:5)

Thou hast shamed this day - Joab's speech to David on his immoderate grief for the death of his rebellious son is not only remarkable for the insolence of office, but also for good sense and firmness. Every man who candidly considers the state of the case, must allow that David acted imprudently at least; and that Joab's firm reproof was necessary to arouse him to a sense of his duty to his people. But still, in his manner, Joab had far exceeded the bonds of that reverence which a servant owes to his master, or a subject to his prince. Joab was a good soldier, but in every respect a bad man, and a dangerous subject.

- Adam Clarke's Commentary on the Bible