1 Kings 2:31-33

31The king replied to him, "Do as he has said, strike him down and bury him, and thus take away from me and from my father's house the guilt for the blood that Joab shed without cause.

32The Lord will bring back his bloody deeds on his own head, because, without the knowledge of my father David, he attacked and killed with the sword two men more righteous and better than himself, Abner the son of Ner, commander of the army of Israel, and Amasa the son of Jether, commander of the army of Judah.

33So shall their blood come back on the head of Joab and on the head of his descendants forever. But for David and for his descendants and for his house and for his throne there shall be peace from the Lord forevermore."