A wise son maketh a glad father: but a foolish man despiseth his mother.
– Proverbs 15:20
[T]he word for glad means to brighten, or cause to rejoice. A son receiving and walking in wisdom makes a father glad. This is a persistent theme in Proverbs (Proverbs 10:1; 23:15-16; 29:3). Parents cannot make their children wise, but they continually instruct and correct in hope they will receive wisdom. When the children receive correction and instruction, parents are blessed in numerous ways and rejoice. The contrasting line is a different perspective than the usual. The focus is not as much on the effect on the mother, but rather on the son who is foolish. Such a man is hardened and dishonors his parents (Proverbs 23:22; 30:17), and sins against God (Exodus 20:12; Leviticus 19:3).