Take a cenus of all the tribes of Israel - so I may know how may people there are - 2 Samuel 24:2
It is apporopriate and even necessary to speak words of correction, even when those words are not warmly received
Joab spoke up to King David, "Why do you want to do this?" - 2 Samuel 24:3
Why must you cause Israel to sin - 1 Chronicles 21:3
Joab apparently understood that David's orders came out of his reliance on superior military strength rather than the might of heaven
Though Joab warned King David not to go through with the cenus, the king did it anyway and paid a terrible price