Taoism way of fasting
The Causes of Fasting:
Fasting is one of the principal tasks in Taoists' daily religious practice. The aim is for pious Daoists to keep their body clean and their soul pure. Fasting existed long ago in ancient China. The Book of Changes claims that to fast is to take preventive measures against wrong-doings to reform oneself thoroughly. In the book Mencius it is written: "Even a villain can worship the Higher Emperor so long as he fasts." Records about fasting can also be found in several chapters of the Book of Rites. It is recorded that to fast is to commune with spirits and ghosts. As one is going to fast, he must guard against everything evil and get rid of hobbies and desires. It would be better not to listen to music, not to worry about anything, and not to move with one's hand and feet." Taoism inherited the skill of fasting for the purpose of restraining Daoists and to offer sacrifice to the spirits as well as to Heaven and Earth.
The Book of Esoteric Explications of the Three Heavens written in the Liu Song dynasty of the epoch of division between South and North said: "To learn Tao, one must fast first. Thus one can keep one's body clean externally and one's mind empty and pristine internally, so much so that one ascends while the Perfected descend. Finally he and Tao will be one. A long time of fasting can help one communicate with the Perfect Tao without violating any taboos."
Since the Tang and Song Dynasties, fasting has been closely connected with chanting scriptures, which has become a part of Taoists' routine practice. The Collected Annotations of the Book of Salvation wrote that if one persists in fasting, burning joss sticks and chanting scriptures, one is sure to be rewarded with boundless fortune, for he has accumulated so many merits and virtues. On the one hand, fasting is powerful enough to eliminate natural disasters and ensure the king's throne as well as blessings for the state. On the other hand, it can put an end to various poisons and save the common people from misfortunes.
The Functions of Fasting:
Fasting has two functions. Firstly, it is a step to cultivate the Tao. Taoist scriptures state: "Fasting is necessary for a Taoist to cultivate Perfection in a Taoist temple. Be careful about what you say and be prudent so as not to make mistakes. Then you may approach Tao." Taoism believes tha fasting is the root of Tao and the bridge of skills. If one is to cultivate Tao, he must fast and obey the commandments, keep the perfect Tao in one's mind, and then one's evil desires disappear automatically."
Secondly, it is a method of communicating with divines. When it comes to fasting and reciting scriptures, Zhang Yuchu wrote in the Ten Daoist Commandments: "Anyone cultivating Tao must fast for a clean body as well as a pure heart, and he must visualize the divines and read Taoist scriptures silently in his mind. It is as if facing the Higher Emperor, communicating with him with the heart. Once concentrating on it with a pure heart, he will understand the perfect meaning of the Tao. If one reads aloud the scriptures in a clear and melodious sound, the Vital Breath will rise and harmonize smoothly, so one can accumulate merits quickly.
Then the jade sound of reading can nourish the breath with spontaneous inspiration. As a result, Heaven will be peaceful and the Earth safe, and good customs will help the people with fortune collected and misfortune disappeared. But if one recites Daoist books absent-mindedly without any belief in it or without a pious heart, what is the good of reading hundreds or thousands volumes daily? Then how can it be possible to dispel misfortune?
Generally for Taoists, it is encouraged to fast(vegeterian diet) on the first and fifteen day of the lunar month.
On special days, such as divines' birthday, aniversaries and time of rituals, it is important to fast too.
In some scriptures, there are certain days set aside in the month whereby Taoists who are cultivating are encouraged to fast on these unique days.
For Quanzhen Taoist priests who lived in the temple, they need to observe a vegeterian diet. For zhengyi Taoists, only certain group of them observe that, for the others, they only fast during rituals.