It is the undoubted character of every righteous man that he hates lying (that is, all sin, for every sin is a lie, and particularly all fraud and falsehood in commerce and conversation), not only that he will not tell a lie, but he abhors lying, from a rooted reigning principle of love to truth and justice, and conformity to God.
It is crucial both to listen and speak wisely. The wise son is contrasted with the most intransigent of fools, the scoffer. The wise son is teachable, accepting correction from his father.
The incorrigible mocker is so set in his folly that he scoffs at such correction. The mocker is controlled by his sin, therefore his life is loathsome.
The righteous man hates falsehood. Which implies at least that he will not be ashamed and may even be honored for his honesty. Righteousness protects the one whose way is blameless, whereas wickedness leads the sinner astray to his own ruin.