A Prov. 15:5, “A fool despises his father’s instruction.”
A1 Prov. 15:20, “A wise son makes a glad father, but a foolish man despises his mother.”
B Prov. 15:5, “but whoever heeds reproof is prudent.”
B1 Prov. 15:21-22, “Folly is a joy to him who lacks sense, but a man of understanding walks straight ahead. Without counsel plans fail, but with many advisers they succeed.”
These two concepts are connected. If you reject your parent’s instruction today, you are more likely to reject other people’s direction tomorrow. Your attitude towards your parents’ advice will likely determine your attitude to other people’s advice.
Your parents aren’t perfect. They’re not right all the time. But they’re right most of the time. Your parents have been there way ahead of you. They know better, having learned many painful lessons in life. You will be wise to listen and follow their instruction.
In v. 21, the fool is one who lacks understanding and wisdom. But the wise is one who “walks straight ahead.” To word, “straight” (Heb. yashar), means, “upright” in the ethical sense (BDB); or to be honest, just, or righteous. Thus, the wise lives an upright, ethical, just, and righteous life.
Now if you don’t follow your parents’ advice, you are like the fool who rejects wisdom. But if you follow them, you are wise, walking uprightly.
In v. 22, plans fail if made by only one person. There is no second or third eye to see any defects. Hence, we should be willing to listen to the counsel of many. Their advice will improve your plans.
This New Year, you will make plans. Listen to the advice of others. Don’t be independent, as if you know it all. Read the wisdom of the more learned and experienced. (That’s why Pastors who don’t read are not wise. They don’t learn from others.) Learn from their mistakes and their successes. If you do, your plans will succeed.
 Garrett, Proverbs, 151.