From my book, As The Mood Prescribes.

 

A quiet pond a mirror makes,

reflections true there lay.

A tranquil mind, a mirror too,

where peace and calm array.

A pebble tossed into the pond

will stir and spoil that scene.

A seed of doubt within a thought

can soil that once serene.

Let not the winds of worry,

nor wistful waves of woe,

distort the mirrors echo

that comes from deep your soul.