Matthew Henry Presbyterian @wholebiblehenry

See here, 1. How formidable kings are, and what a terror they strike upon those they are angry with. Their fear, with which (especially when they are absolute and their will is a law) they keep their subjects in awe, is as the roaring of a lion, which is very dreadful to the creatures he preys upon, and makes them tremble so that they cannot escape from him.

John Gill Reformed Baptist @doctorgill

The fear of a king is as the roaring of a lion,.... The wrath and displeasure of a king, which causes fear; see Pro 19:12; kings should be terrors to evil works and workers, though not to good ones, Rom 13:3.

Jamieson-Fausset-Brown Reformed @jfbcommentary

(Compare Pro 19:12). Men who resist authority injure themselves (Rom 13:2).