Wooden fish, commonly called mu-yu in Chinese transliteration, is an
implement for worship during singing in praise of the Buddha. A piece
of wood hard and solid is carved such that it is hollowed, rounded on
one end, and with a handle on the other. Once hit, it emits a potent
low-toned sound as reminder for those heeding. To the analogy of a
fish in water not ever breaking, not ever closing its eyes, the wooden
fish is there to spur everyone to refrain from indolence, to seize time
for continual practice.