The Lord used Jehu to pay back to the house of Ahab all the evil that he had committed. Therefore, Joram, also known as Jehoram, a descendent of Ahab, suffered at the hands of Jehu,

Then Joram turned around and fled, and said to Ahaziah, “Treachery, Ahaziah!” Now Jehu drew his bow with full strength and shot Jehoram between his arms; and the arrow came out at his heart, and he sank down in his chariot (2 Kings 9:23–24).

Jehu knew that this fulfilled the word of the Lord, because when He says that something shall be, it is, and He also promises that we shall reap as we have sown. Thus, Jehu said,

Then Jehu said to Bidkar his captain, “Pick him up, and throw him into the tract of the field of Naboth the Jezreelite; for remember, when you and I were riding together behind Ahab his father, that the Lord laid this burden upon him: ‘Surely I saw yesterday the blood of Naboth and the blood of his sons,’ says the Lord, ‘and I will repay you in this plot,’ says the Lord. Now therefore, take and throw him on the plot of ground, according to the word of the Lord” (2 Kings 9:25–26).