Pictured: Lu Dongbin (left) receives teachings from Han Zhongli. Transmission from teacher to student is the historical standard of Neidan. Traditionally this was a very serious process, but in modern times many people study Neidan with a teacher in a more open environment. Regardless of how austere training is, it is still required that we receive the teachings truly and be serious about our study and application. Much of Neidan is on a need to know basis since it isn’t possible to explain the whole system without the student already having sufficient experience to understand it. Eventually the direction of practice becomes more obvious, but even if we already have a basic understanding of the correct direction of practice we still profoundly treasure our teacher since they gave us some of the greatest gifts we have in life, especially direction toward becoming a more skillful and better person!!
“吕曰：“小还丹既已知矣。所谓大还丹者，何也？”
Lu asked: after the small change of elixir is complete there is the large change of elixir, what is it?
钟曰：“龙虎相交而变黄芽，抽铅添汞而成大药。
Zhong answered: dragon and tiger mix together and generate the Yellow Sprout, withdraw lead and add mercury to achieve the great medicine.
玄武宫 中而金晶才起，玉京山下而真气方升。
The Xuan Wu Palace center golden crystal rises,
the true Qi rises beneath the Jade Capital Mountain.
走河 车于岭上。
The river wheel travels to the top of the mountain ridge.
灌玉液于中衢，自下田入上田，自上田复下田，后起前来，循 环已 满，而曰大 还丹也。
Irrigate the Jade Fluid in the central thoroughfare, it moves from the lower field to the upper field, them from the upper field it returns to the lower field, rising up the back and descending down the front, circulating around the loop is already full, this is called changing the great medicine.
奉道之士，于中起 龙虎而 飞金晶，养胎仙而生真气，以成中丹，良由此矣。”
Those who hold up the Dao rouse the dragon and tiger in the center and the golden crystal flies, nurturing the fetus immortal and generating the Yang Qi, then the central elixir is formed, this is the good way.”
Comments:
Before introducting the central theme of this chapter I'd like to mention that I've updated some terms on the Neidan terminology page at Qigong project, you can see it here:
https://qigongproject.blog/internal-alchemy-terms/
new terms are Xuan Wu, Kan Gong/Water Palace, Li Gong/Fire Palace, Jin Chang/Gold Crystal, and Huang Ya/Yellow Sprout.
Explanation of text: