2 Samuel 3:26-39

And when Joab was come out from David, he sent messengers after Abner, which brought him again from the well of Sirah: but David knew it not. And when Abner was returned to Hebron, Joab took him aside in the gate to speak with him quietly, and smote him there under the fifth rib, that he died, for the blood of Asahel his brother. And afterward when David heard it, he said, I and my kingdom are guiltless before the LORD for ever from the blood of Abner the son of Ner: let it rest on the head of Joab, and on all his father's house; and let there not fail from the house of Joab one that hath an issue, or that is a leper, or that leaneth on a staff, or that falleth on the sword, or that lacketh bread. So Joab and Abishai his brother slew Abner, because he had slain their brother Asahel at Gibeon in the battle. And David said to Joab, and to all the people that were with him, Rend your clothes, and gird you with sackcloth, and mourn before Abner. And king David himself followed the bier. And they buried Abner in Hebron: and the king lifted up his voice, and wept at the grave of Abner; and all the people wept. And the king lamented over Abner, and said, Died Abner as a fool dieth? Thy hands were not bound, nor thy feet put into fetters: As a man falleth before wicked men, so fellest thou. And all the people wept again over him. And when all the people came to cause David to eat meat while it was yet day, David sware, saying, So do God to me, and more also, if I taste bread, or ought else, till the sun be down. And all the people took notice of it, and it pleased them: as whatsoever the king did pleased all the people. For all the people and all Israel understood that day that it was not of the king to slay Abner the son of Ner. And the king said unto his servants, Know ye not that there is a prince and a great man fallen this day in Israel? And I am this day weak, though anointed king; and these men the sons of Zeruiah be too hard for me: the LORD shall reward the doer of evil according to his wickedness.