In the passage from verses 9 to 16, each line begins with the Hebrew letter Beth. This section is very much about true joy.
Psalm 119.9 How can a young man keep his way pure? By guarding it according to your word.
This verse has followed me since I was a young Christian. I am so grateful for the Norwegian prayer house movement I grew up in, because there we learned to highly value God's Word high and let it control our lives. The psalmist asks a very important question and gave us the right answer: How can a young man live clean? By living in the Word of God and walking in the truths of the Word.
Of course, this truth does not only apply to young people. But young people in their youth for the first time meet all the lusts and desires that can make life impure. In our childhood we were unfamiliar with much of these impure impulses, but in youth we encounter this with full force. Childhood is a time of innocence, but in youth we meet all the temptations that belong to adult human life.