“but the teaching of fools is foolishness.” The Hebrew word for “fools” here is evil (#0191 אֱוִיל). The term evil generally refers to a person who is foolish because they are unreasonable and stuck in foolishness, as Proverbs 27:22 (NASB) indicate: “Though you pound a fool [evil] in a mortar with a pestle along with crushed grain, Yet his folly will not depart from him.
To best understand Proverbs, it is important to know that there are five different Hebrew words that are translated “fool” in different English versions, yet there are some distinct differences between them and it is usually worth differentiating them. There is the naïve person [pethe #06612 פְּתִי], which is often translated as “simple,” “naïve,” or “inexperienced.” There is the evil, and the kecil [#03684 כְּסִיל], and these have so much in common that most scholars simply treat them as synonyms (although one teacher has distinguished them as the “unreasonable fool” and the “stubborn fool,” cp. Kingdom Zoology by Joel Freeman). There is the lutz [#03887 לוּץ], the mocking fool, or more simply, “mocker,” and there is the nabal [#05036) נָבָל], the “godless fool” or sometimes the “committed fool.” It is the nabal who says in his heart there is no God (Ps. 14:1), and so we have generally translated it “godless person” in the REV version. Here in Proverbs 16:22, the subject is the evil, the unreasonable or stubborn fool.
One can tell from reading the wide variety of ways that Proverbs 16:22 has been translated that scholars are not in agreement as to the primary meaning of the verse. Many scholars believe that the sense of the stanza is that it is foolishness to try to instruct a fool, because he or she has no desire to learn. That certainly seems to be supported by many verses that use the term evil for “fool” (cp. Ps. 107:17; Prov. 1:7; 12:15; 14:3, 9; 15:5; 20:3; 24:7; 27:22; 29:9; Isa. 35:8; Hos. 9:7).
Another interpretation is that the verse is saying that instruction that comes to a fool does so through his own folly. That interpretation agrees with our common modern saying, “A person learns from his mistakes.” Although that may be true of the simple or naïve fool, the pethi, that does not seem to be the case with the unreasonable fools, the fools designated by the term evil.
Other scholars believe that the verse is saying that when fools instruct or discipline others, what they teach is foolishness. That is certainly true, and we see that in our schools and colleges today. For example, many atheist teachers teach that God does not exist, which is certainly foolish teaching. However, the scholars who argue against that interpretation of this verse say that when the context is fools, the Hebrew word “instruction,” (or “discipline” #04148, muwcar) always refers to the instruction that is given to them, not the instruction they give to others (Prov. 1:7; 15:5). But that argument is not as watertight as it may seem, because there are only two examples and the context of both is very clear, not like Proverbs 16:22 which can mean a couple different things. Also, it is sometimes the case in Proverbs, as in the rest of the Bible, that a word or phrase will have a different meaning in one verse than it does elsewhere, and therefore the context, scope, and applicability are more important final determiners of meaning than the other uses of a word.
Actually, there is no reason to limit the meaning of this verse to just one interpretation. We believe that this verse is an amphibologia, that is, a single statement that has more than one true meaning. We believe this verse is one of the riddles of the wise (Prov. 1:6). It seems that the thought of the whole verse is that a person who has good judgment (which in Proverbs comes from God) has a source of guidance and strength that brings to him “life” in all its fullness, while fools do not have good judgment, so they pour out folly as “instruction.” Furthermore, trying to teach them good judgment doesn’t work because they have no heart to learn; in fact, they don’t even learn from their own mistakes—they just go on having poor judgment.
Part of the failure of our educational system today is failure to acknowledge the different kinds of fools in the world and admit that some people are unreasonable, stubborn, or godless fools who simply refuse to learn. Those people are allowed to stay in class and disrupt learning for everyone else instead of being disciplined in some effective way that stops them from keeping the other students from learning.