Tetzaveh: Chapter 18
"He knows what is in the darkness"

Rabbi Shimon explains that the title verse means that God revealed profound and concealed things, for were it not for the darkness of the Left, the depths and the concealed things would not be revealed. He says that "the light dwells with Him" refers to the light that has been revealed from within the darkness, and this light was revealed to all of us from the darkness that was in the wilderness.