'Unwise' in the Bible

The wisdom of the man of good sense makes his way clear; but the unwise behaviour of the foolish is deceit.

Their wisdom is a crown to the wise, but their foolish behaviour is round the head of the unwise.

The heart of the man of good sense goes in search of knowledge, but foolish things are the food of the unwise.

Foolish behaviour is joy to the unwise; but a man of good sense makes his way straight.

He who has an unwise son gets sorrow for himself, and the father of a foolish son has no joy.