Someone Left To Speak

I was just at the Quinte Mall in Belleville, Ontario where I saw, and picked up a plaque that read:

I believe in the sun
even when it is not shining,
in love
even when I am alone,
and in God
even when He is silent.

- Inscription found scratched into a wall in Germany by someone hiding from the Nazi concentration camps.

It filled me with both hope and dread. Like a voice from the past raising a warning for the future. Will we ever learn?