Adam Clarke on Amos 5:19

As if a man did flee from a lion, and a bear met him - They shall go from one evil to another. He who escapes from the lion's mouth shall fall into the bear's paws: -

Incidit in Scyllam, cupiens vitare Charybdim.

The Israelites, under their king Menahem, wishing to avoid a civil war, called in Pul, king of Assyria, to help them. This led to a series of evils inflicted by the Syrian and Assyrian kings, till at last Israel was ravaged by Shalmaneser, and carried into captivity. Thus, in avoiding one evil they fell into another still more grievous.

Leaned his hands on a wall, and a serpent bit him - Snakes and venomous animals are fond of taking up their lodging in walls of houses, where they can either find or make holes; and it is dangerous to sit near them or lean against them. In the East Indies they keep the faithful mongose, a species of ichneumon, in their houses, for the purpose of destroying the snakes that infest them.