1 Kings 2:21-25

21“Then let your brother Adonijah marry Abishag, the girl from Shunem,” she replied.

22“How can you possibly ask me to give Abishag to Adonijah?” King Solomon demanded. “You might as well ask me to give him the kingdom! You know that he is my older brother, and that he has Abiathar the priest and Joab son of Zeruiah on his side.”

23Then King Solomon made a vow before the Lord: “May God strike me and even kill me if Adonijah has not sealed his fate with this request.

24The Lord has confirmed me and placed me on the throne of my father, David; he has established my dynasty as he promised. So as surely as the Lord lives, Adonijah will die this very day!”

25So King Solomon ordered Benaiah son of Jehoiada to execute him, and Adonijah was put to death.