2 Samuel 3:31

David said to Joab. The excuse of the blood feud made it impossible for David to punish Joab further than by depriving him of his command; but he made him condemn his own deed by taking part in the public mourning for the man he had murdered. This mourning consisted in going in solemn procession, clad in sackcloth, before Abner's body, carried on a bier to the grave, while David followed as chief mourner; and the emphatic way in which he is called King David suggests the thought that he went in royal state, so as to give all possible dignity to the funeral. His tears and lamentations with uplifted voice were so genuine and hearty as to move the people to a similar outburst of grief. But while all those at Hebron had proof that David was innocent, the people generally would know only that, when Abner was escorting the king's wife back to him, and arranging for his election to rule over all Israel, he was treacherously murdered at the gate of Hebron by one who was chief over David's army and also his nephew.