Hooks in thy jaws. — An allusion to the ancient way of taking and destroying the crocodile, otherwise invulnerable to their arms.
Fish of thy rivers shall stick unto thy scales. — As the crocodile, the lord of the Nile, represents the royal power of Egypt, so the fish represent the people dependent upon him. Pharaoh is not to fall alone, but shall drag his people with him into a common ruin.