This song by Suzanne Toolan RSM is in the Taizé style, which is hardly surprising as she has written for Taizé and the refrain was suggested to her by phone by Brother Roger from Taizé.
The ostinato refrain is sung and the cantor sings the verses over the choir/assembly.
The sheet music can be purchased for download at OCP, where you can see the text in the preview. The original can be heard here.
My backing has both melody lines running.