The Taoists believe that our present bodies are an illusion and a transitory vehicle. Whether you choose to be buried or cremated after you die makes little difference because the physical matter of our body will eventually be completely disintegrated with the passage of time. Our physical existence is really very short. A hundred years is equivalent to roughly 30,000 plus days. However, based on the evolution and development of the human species – the human structure and metabolism – every person should have no problem living to 150 years, provided that their existence is in total harmony with nature. If one does not live in accordance to the rhythms of the heavens, then their physical life will be greatly shortened. Even though Master Lv Zhu (吕祖) pointed out that our bodies are an illusion, it is a reality that all of us also possess a little amount of Ling Qi (灵气) inside our body. This Ling Qi is like the Gu Shen (谷神) found within the deepest mountain valleys and it moves within our hearts and bodies. We do not hear her and cannot see her, so we cannot determine where she is, just as our physical internal organs and skeletal systems are very real and exist within us, yet most of us have no awareness of them. And this total lack of self awareness is the root cause of why we take our bodies for granted and abuse our bodies on a daily basis. It is a great tragedy that we do not hear her or know what she is doing or when she begins her rhythmic movements (regulated or not regulated). The moment she stirs, opens up and moves is when the mysterious gate of the heaven and earth (玄牝) appears.
So all 3 types of Bi Gu make use of the 3 types of energies. The interchanging and transformation of these 3 energies with one another requires our Ling (灵) as the medium to conduct the various processes. Every one of us possesses this Ling, even the dead. In fact, dead people rank highest since there is no more physical movement coming from them and therefore the Ling can manifest herself completely before finally retreating away from the body. It is when the Ling completely leaves the body that one is considered completely dead (神得一以灵, 一是太乙, 本体得太乙以为灵. 全灵而退才是死人).
Master Lv Zhu (吕祖) summarizes the practice of Bi Gu as follows:
“A proper Bi Gu means to accomplish the following: to cease the intake of physical foods (断精食), to accumulate the Jing Qi (聚精气) and to return the Shen back to oneself (神归己), to place the Ling within the internal Qi (灵入气中为辟谷).” Bi Gu goes against one’s normal daily routine and habits because humans predominantly rely on physical foods (which can be further categorized into different types) for their daily sustenance.
Retreats can be further divided based on their purpose, e.g. Life and Death Retreats. The Master Wang Zhong Yang (王重阳) is the most proficient practitioner of this type of retreat. When he felt that his Ling was not completely manifested, he made a grave for himself and lived like a dead person. Even the dead have feelings, thoughts, and can communicate.
Bi Gu also involves moving from a post-natal state to a pre-natal state. The number for females is 7 and the number for males is 8. So we have this equation: Yin Yang and the 5 elements = 7 X 8 X 5 = 280 days. For females 7 X 3 = 21 days and for males 8 X 3 = 24 days. The basic number for male and female = 7 X 8 = 56 days. Combined together to form a fetus we have 56 X 5 = 280 days; this is the duration the fetus is in the mother’s womb. The monthly period for females is 28 days and multiplied by 10 months, we also get 28 X 10 = 280 days.
Once again, it is important to know the purpose of a Bi Gu so that the practitioner is able to achieve certain meaningful changes at the end of the practice. Otherwise, it is nothing more than starvation.