C. F. Keil and Franz Delitzsch on 1 Kings 1:51-52

1Ki 1:51-52

When this was reported to Solomon, together with the prayer of Adonijah that the king would swear to him that he would not put him to death with the sword (אם before ימית, a particle used in an oath), he promised him conditional impunity: “If he shall be brave (בּן־חיל, vir probus), none of his hair shall fall to the earth,” equivalent to not a hair of his head shall be injured (cf. 1Sa 14:45); “but if evil be found in him,” i.e., if he render himself guilty of a fresh crime, “he shall die.”