1 Corinthians 1:1-9
I've posted quite a few songs about light. Please do a search (to the right) and you'll find all of them there.
Here's a cool song that I think if adapted/arranged could be a great chant piece.
AND, if you've not seen The Concert for George, do. It is a beautiful, loving and joyful musical tribute. Amazing really.
Inner Light by George Harrison