1 Kings 2:21-24

21So she said, “Let Abishag the Shunammite be given in marriage to your brother Adonijah.” 22King Solomon answered his mother, “Why do you request Abishag the Shunammite for Adonijah? You might as well request the kingdom for him—after all, he is my older brother—yes, for him and for Abiathar the priest and Joab son of Zeruiah!” 23Then King Solomon swore by the Lord: “May God deal with me, be it ever so severely, if Adonijah does not pay with his life for this request! 24And now, as surely as the Lord lives—he who has established me securely on the throne of my father David and has founded a dynasty for me as he promised—Adonijah shall be put to death today!”