Try to understand: darkness comes from light. When no light is visible, then we are in darkness. Clouds are not to be found in the sun; that would be against the nature of the sun. But by the energy of the sun other things are temporarily created, such as mist, clouds or darkness. These creations are temporary, but the sun remains. Similarly, material nature is temporary, but spiritual nature is permanent.
The Tenth Morning Walk, May 14, 1973, Recorded In Cheviot Hills Park, Los Angeles