1 Kings 2:6-9

6Therefore do according to your wisdom, and do not let his gray hair go down to the grave in peace.

7“But show kindness to the sons of Barzillai the Gileadite, and let them be among those who eat at your table, for so they came to me when I fled from Absalom your brother.

8“And see, you have with you Shimei the son of Gera, a Benjamite from Bahurim, who cursed me with a malicious curse in the day when I went to Mahanaim. But he came down to meet me at the Jordan, and I swore to him by the Lord, saying, ‘I will not put you to death with the sword.’

9Now therefore, do not hold him guiltless, for you are a wise man and know what you ought to do to him; but bring his gray hair down to the grave with blood.”