1 Kings 2:21-24

21And she said, Let Abishag the Shunammite be given to Adonijah thy brother for a wife. 22And king Solomon answered and said to his mother, And why dost thou ask Abishag the Shunammite for Adonijah? ask for him the kingdom also; for he is my elder brother; even for him, and for Abiathar the priest, and for Joab the son of Zeruiah. 23Then king Solomon swore by the LORD, saying, God do so to me, and more also, if Adonijah hath not spoken this word against his own life. 24Now therefore, as the LORD liveth, who hath established me, and set me on the throne of David my father, and who hath made me an house, as he promised, Adonijah shall be put to death this day.