All Scripture is inspired by God and is useful to teach us what is true and to make us realize what is wrong in our lives. It corrects us when we are wrong and teaches us to do what is right. God uses it to prepare and equip his people to do every good work.
A good person produces good things from the treasury of a good heart, and an evil person produces evil things from the treasury of an evil heart. What you say flows from what is in your heart.
And you must commit yourselves wholeheartedly to these commands that I am giving you today. Repeat them again and again to your children. Talk about them when you are at home and when you are on the road, when you are going to bed and when you are getting up.