Charles Ellicott Commentary 1 Kings 1:52

"And Solomon said, If he shall show himself a worthy man, there shall not a hair of him fall to the earth; but if wickedness be found in him, he shall die." — 1 Kings 1:52 (ASV)

There shall not a hair of him fall—Solomon’s pardon, though an act of extraordinary grace according to Eastern customs, was yet characteristically cautious and conditional, to be withdrawn accordingly at the first sign of any renewal of Adonijah’s claims.