Marvin Wilson, author of Our Father Abraham, has written incisively about the various meanings for our word "fool:" "In Biblical wisdom literature the pupils of the sages and mentors are the unwise, often termed "fools" (Proverbs 1:7) or "simple one" (1:22). In wisdom literature the different levels of fools-both young and old-are the raw material on which the sages had to work and they represent the varying degrees of rawness. Perhaps as much as anything else, the term fool is descriptive of an attitude, bent of mind, or direction in life which needs correcting. The various Hebrew words for "fool" occur more than a hundred times in the book of Proverbs."
This was not necessarily a negative term. A simple fool, or "peti," was a person who made mistakes but quickly righted them and was restored to fellowship with God and with others. When I started correcting the way I was handling finances in my business, I could visibly see God's hand begin to work on my behalf. I began getting unsolicited calls for business. My staff began working as a team. We were seeing God's blessing in our business again and I began to once more hear God's voice. I never realized how much I had been walking away from His umbrella of protection until I woke up one day realizing I had a financial crisis. I knew I had not experienced a closeness to God in many years, but had never really known why. My financial crisis was God's reproof for me. It was His loving discipline for me to bring me back to Him. It was a loving act of God.
The hardened fool "kesil and ewil", makes mistakes but never learns from them and will not listen to others. This person can expect God's reproof to continue and will eat the fruit of his own way (see Proverbs 1:31,32). The hardened fool "returns to his own vomit." David was a simple fool. He made many mistakes but he was quick to repent of them. King Saul was a hardened fool, one who made mistakes but went back to making the same mistakes. We're going to make mistakes. The question is, once we know we have made a mistake before God, do we make the necessary adjustments that will allow Him to intervene on our behalf? And will we avoid those same mistakes? God says that if we do, He will pour out His Spirit on us (see Proverbs 1:23). He will make known His words to us.
The third level of fool mentioned in the proverbs is the mocking fool or "letz". The mocking fool mocks the things of God. This word means "scoffer" or "scorner."When you encounter cynical people who disregard the things of God, you know these people are "mocking fools."
The fourth level of fool that we encounter is the God-denying fool or "nabal". The term relates to the morally wicked who ignores the disgrace he brings on his family and despises holiness (see Proverbs 17:21). This person says, "There is no God." By failing to acknowledge God for Who He is, the nabal declares himself to be a "God-denying" fool.
I have found it is helpful to try to understand if people are teachable. Are they simple fools, those who make mistakes but seek to learn from them? I can work with those people. But if I sense I am working with a hardened fool, I know I should not spend much time on that person. Jesus did not spend much time trying to convince the rich young ruler. He presented truth and let him make his decision. Some people must get broken before they can become simple fools.