One of his disciple Swamis asked, "When you see a movie, what is the most important thing?" We answered, "the characters!", "the plot!", "the scene?" The Swami replied, "The screen. Without the screen you have nothing to project the movie upon."
In the Sivananda yoga tradition, this is a classic. I remember when I learned this, that I didn't like how the Swami knew the answer but let us guess like little kids. This explanation did though, make an impression on me.
Now, in my own confusion I like imagining the simplicity and cleanliness of an open space, a blank screen, and of something that never changes itself, but change happens upon it. Its like contemplating infinity, seeing beyond the stars, or looking into deep water. A very small and very big feeling all at once.