This phrase represents the meaning of the connecting and reflecting aspect of reality. There is a resonance between the higher worlds, and the physical plane. They mirror one another like our world mirrors the universe. When you meditate you want to be aware of this so that you know that these worlds impact one another. There are many people who feel you should work on your outer world to change your inner world, and vice versa. I feel it is actually best to use both methods. Feel the connection between your ability to impact things from each plane so that you are familiar with the energy of working in each energetically. It is really important to have a sense of wholeness and not fracturing the spirit when doing spiritual growth. Many spiritual people struggle with staying grounded. This often happens when we develop spiritually, but should not be a long lasting pattern. Just being aware of the breath can put the higher plane and the earth realm in harmony.