1 Kings 2:4-6

4and so that the Lord will fulfill his promise that he made to me: ‘If your sons take care to walk faithfully before me with all their heart and all their soul, you will never fail to have a man on the throne of Israel.’

5“You also know what Joab son of Zeruiah did to me and what he did to the two commanders of Israel’s army, Abner son of Ner and Amasa son of Jether. He murdered them in a time of peace to avenge blood shed in war. He spilled that blood on his own waistband and on the sandals of his feet.

6Act according to your wisdom, and do not let his gray head descend to Sheol in peace.