1 Kings 2:8-9

8“Shimei, son of Gera from Bahurim in Benjamin, is still with you. He cursed me repeatedly when I went to Mahanaim. But when he came to meet me at the Jordan River, I took an oath by the Lord and said, ‘As long as I’m king, I won’t have you killed.’

9Now, don’t let him go unpunished. You are wise and know what to do to him: Put that gray-haired, old man into his grave by slaughtering him.”