1 Kings 2:22 (KJV)

Then she said, I desire one small petition of thee; I pray thee, say me not nay. And the king said unto her, Ask on, my mother: for I will not say thee nay.

And she said, Let Abishag the Shunammite be given to Adonijah thy brother to wife.

And king Solomon answered and said unto his mother, And why dost thou ask Abishag the Shunammite for Adonijah? ask for him the kingdom also; for he is mine elder brother; even for him, and for Abiathar the priest, and for Joab the son of Zeruiah.

Then king Solomon sware by the Lord, saying, God do so to me, and more also, if Adonijah have not spoken this word against his own life.

Now therefore, as the Lord liveth, which 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.