The deities most commonly worshipped were, in fact, the three kinds: Heaven, Earth, and Water.
Heaven meant the gods of the four seasons, while Earth and Water referred to local mountain gods, land gods, water gods, and the like—all of them belonging to the Earthly Deities.
For the four seasons and the mountains and waters were necessary conditions for the production and lives of all people. Without them, people could not survive, so they always held them in awe and worshipped them with sincere reverence.
The rites recorded in Zhu's Path, for instance, stated: "When sacrificing to Heaven, burn firewood; when sacrificing to mountains, rivers, and hills, raise offerings; when sacrificing to rivers, sink them; when sacrificing to Earth, bury them."
Water was the blood and vital breath of the earth, flowing freely like veins and arteries.
Water was the measure of all things, the wellspring of all life, the substance underlying right and wrong, gain and loss. Thus there was nothing it could not fill, nowhere it could not abide. It gathered in Heaven and Earth and lay hidden within all things; it arose from gold and stone, yet gathered within all living beings.
In other words, water was the "foundation" of all things, the "center" of all life, and the basis of all right and wrong, gain and loss. Therefore, there was nothing it could not fill, nor any place where it could not linger. It could gather in the sky and upon the earth, be contained within all things, arise from gold and stone, and yet fill the bodies of all living beings. Thus, it bore a duty much like the blood of the earth.
This nature of water determined the nature of water deities.
Water deities needed to transport the provisions of Heaven and Earth. Like