Psalm 19:8: “The precepts of the Lord are right, giving joy to the heart. The commands of the Lord are radiant, giving light to the eyes.”
God instructs us and this has impact on our lives. On the one hand these instructions direct us. That is exactly what is meant by ‘giving light to the eyes’. People walk in spiritual darkness, because they do what they want to do and are led by their sinful understanding of what is right and wrong. God’s word enlightens us and we see which direction we should go.
On the other hand, this holy guidance gives joy to our hearts. It is not what most of us imagine. We think that when we hear the word of God we should be sorrowful and unhappy. No, God gives us joy when we listen to His instructions. It is our part to submit ourselves for those. So, be glad when you are instructed by the word of God.