 Every other line, every other verse in Psalm 23, in some way, shape, or form, accentuates, amplifies on the central theme, the Lord is my shepherd. It's almost as though, use your imagination here, it's almost as though David as a sheep is looking at the shepherd. He's looking at the Lord Jesus, and what he does in Psalm 23 is that he's telling us something that's true about the great shepherd of the sheep, and he's telling us what he does for us as sheep.