The other day at mass, they sang We are the Light of the World by Jean Grief. That's a folk song, based on the Beatitudes. It's a pretty nice one. I like it.
Call me crazy, but I could swear that when I was growing up, it was sung "you are the light of the world". I kept on unintentionally slipping into the second person, while singing it. Hearing it in the first person for the first time...well, it sounded a little braggy, like we're singing about how amazing we are. I wonder if it was just my church growing up that changed the lyrics, or if I'm remembering it wrong.
Also, the Biblical passage which the lyrics are echoing are mostly in second person; "In the same way, let your light shine before others, that they may see your good deeds and glorify your Father in heaven." (Matthew 5:11)