This saying is a great metaphor for meditation. Have you ever looked at one blade of grass, without moving for sometime? After time you could see every small movement on the ground, not only where you are focussing, but all over your peripheral vision. It’s almost as if you can see the grass growing… well, not quite, but you get it.
When we meditate our mind is like the ground, our vision like our consciousness. When we keep one-pointed, our mind becomes clear to us, we can see it clearly and all its twisting and turnings. We can see it writhing under the focus of our undivided attention. Any little movement is detectable. Seeing it, we can repair it over the course of time.
Just a little thought. Kept it short for you.