Our hearts are begging us to seek the face of God. It’s what we were designed to do, and it’s where so much idolatry happens. In our flesh, we try to fill that emptiness and longing with lots of other things. David recognizes that his heart is pointing him to Yahweh, and so the one thing he wants more than anything else is not deliverance from his enemies, perfect health, or long life; he wants to live every single day of his life in the presence of God.
Jesus told the people of his day: "I am the light of the world. Anyone who follows me will not walk in the darkness, but will have the light of life." Jesus isn't one of several lights, the lighting section of Menards or Lowes. He's THE Light of the World, which means, if the world with all it's darkness is ever going to have light, it'll only be through him.