2 Kings 10:14-15

And he said, Take them living. So they took them living, and put them to death in the water-hole of Beth-eked; of the forty-two men he put every one to death; And when he had gone away from there, he came across Jehonadab, the son of Rechab: and he said good-day to him, and said to him, Is your heart true to mine, as mine is to yours? And Jehonadab in answer said, It is; and Jehu said, If it is, give me your hand. And he gave him his hand, and he made him come up into his carriage.