The Mirror of Zen

Commentary

Any lute player can tell you that the strings of a harp must be
properly tuned-neither too tight nor too loose-in order to make
beautiful music. Practicing meditation follows the same principle.
Impetuous practice makes you overstimulated and distempered
while slackened practice leaves you dulled and vague, and
leads you right into the cave of demons. When your practice is
neither too "slow" nor too "fast," you will find the mysteriously
subtle balance in it.