What does Proverbs chapter 3 mean?

Proverbs 23:17,18 KJV

Let not thine heart envy sinners: but be thou in the fear of the LORD all the day long, for surely there is an end (a hereafter) and thine expectation (hope) shall not be cut off.

A son is being warned to not mistakenly envy what might appear appealing in what those who disobey God are doing, but instead he is to fear the consequences that necessarily will come from Yahweh for evil behavior. Such fear of consequences should guide your behavior all day long. Then that which you should attain by right behavior will not be taken away from you. You will not lose the good things that you hoped for.