This rather illuminating object lesson illustrates just how invincible the Light of the World is.
It also lends itself to the explanation of the death and resurrection of Jesus.
Themes:
Jesus as the Light of the World, the death and resurrection
Bible text:
In him was life, and that life was the light of all mankind. 5 The light shines in the darkness, and the darkness has not overcome it. (John 1:4-5)