If our ordinary, self-centered viewpoint is dominant, rocks and tree roots are undesirable. But if we change our point of view, then the very fact that there are rocks and tree roots makes the valley stream more beautiful and the sight of waves breaking upon them beyond description. When we perceive joy, anger, happiness and sorrow as enriching our lives, just as rocks and tree roots and water spray embellish nature, then we are able to accept whatever happens and live like flowing water, without clinging to anything.
The fitness of our hearts and thoughts to receive God's spirit is like that of violin strings. If they are properly tuned, in harmony with one another, then the touch of the bow produces beautiful music. If not, then there is only discord. Whenever our hearts are truly ready to receive God's spirit, they will produce heavenly airs and joyous harmonies -- both in this life and in the spiritual world.