I think The Light is suitable for ages four to adult. It is perfect to read to young children, accessible for early readers and simply beautiful for adults.
There is great beauty in the text. Its simplicity belies a deeper meaning. Let the words sink into your soul. “There are days of clouds and … of sun. Through it all, the Light shines.” Jesus, the Light of the world never leaves us, no matter how awful our external circumstances seem, He is right there beside us.