Dogen Zenji said:

Enlightenment is like the moon reflected on the water.
The moon does not get wet, nor is the water broken.
Although its light is wide and great,
The moon is reflected even in a puddle an inch wide.
The whole moon and the entire sky
Are reflected in one dewdrop on the grass.

The moon & water are powerful, ubiquitous, emblems in Zen.

The Japanese have a saying, one does not fall in love by looking at one's lover...but by each seeing the moon together.