23Then King Solomon swore by the LORD: “May God punish me, and ever so severely, if Adonijah has not made this request at the expense of his life.
24And now, as surely as the LORD lives — the One who established me, who set me on the throne of my father David, and who founded for me a dynasty as He promised — surely Adonijah shall be put to death today!”
25So King Solomon sent the order to Benaiah son of Jehoiada, who struck down Adonijah, and he died.
— 1 Kings 2:23-25