Vocal Prelude

I am looking for a song for my vocalist to sing as a Prelude. Our wedding will be in a Lutheran Church and my Pastor is pretty open. But I can`t seem to think of an appropriate song.....any ideas?
The processional is going to be Pachabel and I`m coming in to the traditional Wedding March(which I realize is now dated but I have been dreaming about my wedding since I was ten and it always had the Wedding March in it). Any help would be greatly appreciated! Thanks