This is more of a solo song than a congregational piece, though the chorus is very easy to pick up and sing and this could be done by a soloist on the verses and then the congregation joining in on the refrain. 

But for the most part this song of David LaMott'es is on the site as a "Singer/Songwriter (Solo) piece just for listening and for the beautiful message and artistry.   The lyric of the refrain is attributed to St. Francis:  "All the darkness in the word can't extinguish the light of just one candle."