What is a fool?
A fool is one whose heart turns continually toward foolishness. "Fools speak foolishness and make evil plans" (Isaiah 32:6). Proverbs 26:11 says, "As a dog returns to its vomit, so fools repeat their folly." Fools do not learn their lessons from the mistakes they make. They continue doing the same foolish things to their own destruction (Proverbs 18:7).
The following is a partial list of some characteristics of a fool from the book of Proverbs. A fool hates knowledge (1:22), takes no pleasure in understanding (18:2), enjoys wicked schemes (Proverbs 10:23), proclaims folly (Proverbs 12:23), spurns a parent's discipline (15:5), speaks perversity (19:1), is quick-tempered (12:16), gets himself in trouble with his proud speech (14:3), mocks at sin (14:9), is deceitful (14:8), and despises his mother (15:20). A foolish child brings grief to his or her parents (17:25; 19:13). A foolish man commits sexual immorality (6:32, 7:7-12). A foolish woman tears down her own house (14:1).
The ultimate description of a fool is one who "says in his heart, 'There is no God.' They are corrupt, and their ways are vile; there is no one who does good." (Psalm 14:1, 53:1). Although fools can choose to become wise by learning from the wise and applying it (Proverbs 8:5, 21:11), the Bible warns against associating with fools (Proverbs 14:7). Proverbs 13:20 says, "Walk with the wise and become wise, for a companion of fools suffers harm."
The bad news is that there are fools all around us who have no intention of changing their ways. The good news is that you don't have to be one of them.