29 He that troubleth his own house shall inherit the wind: and the fool shall be servant to the wise of heart.

A cruel person that does not do his job as part of the family will end up with nothing. He will also end up as the employee or servant of the person acting in wisdom.

30 The fruit of the righteous is a tree of life; and he that winneth souls is wise.

A person living a righteous life is not only of benefit to himself but to all around him. He can feed other souls and encourage them to act righteously as well.

31 Behold, the righteous shall be recompensed in the earth: much more the wicked and the sinner.

We will reap what we sow.  Righteous acts will bring the favor and blessing of God. Wicked acts will bring exponential pain to the person.