《玄和子十二月卦金诀》

When the first line of the Fu hexagram (Return, one of the sixty-four hexagrams of the Zhouyi, symbolizing the first stirring of renewed Yang qi) gives rise to a single Yang line, then at the hour of Zi (midnight) the season of alchemical refining turns in step with the cycle of Heaven.

The Fu hexagram governs the eleventh month, and its single Yang line at the bottom signifies the first birth of the elixir. Here the eleventh month is regarded as the start of early spring, the time when work begins. Therefore the method of returning the elixir (the process of refining it and bringing it back to its source) at the hour of Zi must follow the Tiangang (the Heavenly Handle, the law of motion symbolized by the Northern Dipper) in applying the fire. Xuanhezi uses this hexagram image to explain the method of cultivation.

Whoever tends the Golden Cauldron (the vessel used in alchemy, also the furnace and cauldron of Neidan, or internal alchemy) must possess refined and subtle skill. Fast the body and mind, keep yourself pure and still, and serve the Jade Emperor with reverence. All who cultivate the elixir during the twelve inner prohibited days (twelve days of restriction designated by this method) should be masters of the mysterious arts. They must act with cleanliness and respect, as though standing before the Jade Emperor, a lofty perfected being (a high-ranking divine figure revered in Daoism).

The White Tiger and the Azure Dragon are both within the cauldron. The White Tiger belongs to Metal, but has not yet been fully subdued; the Azure Dragon, from this point on, gradually begins to soar. While the Dragon remains unrestrained, one must nourish it slowly with a gentle fire (a mild degree of heat), so that it may rise little by little. In this passage, the original text repeats the same lines.

Since ancient times, the immortals have secretly transmitted one and the same Dao. Who says the returned elixir has some other art? What the sages of earlier ages and the saints of later times handed down is still one and the same path, with no other principle; only the names given to the methods of the elixir differ.

At the time of the Lin hexagram (臨卦, Lin Gua), the fire phase gradually strengthens, like a Red Dragon coming into view. This is mid-spring, with a fine, hazy rain. The so-called "Red Dragon" means that the second line of the hexagram begins to grow, and the heat of the fire steadily increases. The Azure Dragon rises and descends, like shapes faintly glimpsed through rain and mist. The waves on the sea slowly calm, and the towering island of Penglai seems to settle into stillness. The doors of the furnace must be quietly shut to block the wind that slips in through the cracks. The furnace has a door, and the door has a leaf that must be opened and closed at the proper times to prevent drafts. Lead, mercury, and the other symbolic materials used in alchemy must first be properly combined according to the oral formulas before they can be employed in the stage of the ascending hexagram. When blending them, one must master the fire phase and allow no error, so that the elixir can form and attain its subtle efficacy. Only one who understands the numerical principles of the transformations of Qian and Kun (Heaven and Earth, Yin-Yang) can thereby find the road to the Three Pure Ones (Sanqing, the realms of the Daoist Three Pure Ones).

When the Tai hexagram (泰卦, Tai Gua) arrives, the Yin and Yang Qi (qi) draw into balance, and the transformations within the cauldron gradually become apparent. The sounds of the dragon's chant and the tiger's roar can be heard clearly, like lightning racing and thunder surging, growing ever more fierce. The Azure Dragon and the White Tiger interact and transform within the cauldron. The practitioner listens intently to the sound within, like the cry of an infant, and adjusts and masters the fire phase accordingly. The fire is like stored-up lightning and thunder, and then gradually turns into the martial fire (wuhuo, a more intense fire phase).

As spring draws to a close, the north gate of the furnace must be shut. The fire grows stronger and its glow lights up the furnace walls. The "city" here refers to the furnace, meaning that the furnace is to be guarded as one would guard a walled city. And how many people truly understand this secret of long life? Most people covet fame and profit and are busy with worldly affairs; among ten thousand, scarcely one understands this Way of the elixir (Dao). If a practitioner completes the elixir and has also accumulated hidden merit (yin gong, merit gained through secret good deeds), they will in the future ascend to the realm of Jade Purity (Yuqing).

When the first line of the Zhuang hexagram arrives, what is the state of the practitioner's cultivation? The furnace fire grows steadily stronger, and the red clouds of vapor gradually multiply.

The imagery of Neidan (internal alchemy) here corresponds to the four Yang lines of the Zhuang hexagram. It marks the beginning of summer and also signals the fire shifting from gentle heat to intense heat, which is why the text speaks of "abundant red clouds." The sun and moon within the vessel refer to the two Qi of Yin-Yang, which revolve according to their proper seasons and keep to the rhythm of the times. Inside the cauldron, transformations unfold of their own accord, like wind and thunder surging, lead and mercury churning, and emerald waves taking shape. Here the "cauldron" is a symbol of the alchemical process, while "lead and mercury" are Neidan terms that stand for the transformations of Yin and Yang essence and Qi during cultivation.

Listen closely, and gradually you can make out the faint sound of the fire's phasing. At times one nods in acknowledgment, as if approving of the swirling smoke. This is what is meant by Lord Luo of the Fire Star (Huogang Luo Gong): when he hears water dripping inside the cauldron and the furnace fire at its smelting, he knows that the Azure Dragon (a Neidan term referring to the related Yang Qi or medicinal substance) is being brought under control and that the transformation of the elixir has begun to take effect.

Looking further, the Returned Elixir is about to be completed. Among the thousand scriptures and ten thousand oral instructions, none offers a method more exalted than this. Whenever one hears a sound like boiling fire from within the cauldron, it signals that the elixir is gradually ripening, and this means the cultivation has reached a stage that can hardly be surpassed.

The Guai hexagram (夬, Guai) falls in the middle of summer, when the weather is warm. Its single Yin line will not linger for long and will soon become the pure Yang hexagram Qian (乾). Guai is made up of five Yang lines and one Yin line, and it symbolizes the mid-summer stage of the alchemical process. Around the Si hour (巳時, roughly 9 to 11 a.m.) it turns into Qian. This is why the text says the Yin line vanishes quickly and the Qi (vital energy) of pure Yang reaches its peak.

At this stage, subduing the White Tiger (a term from alchemy, often referring to Yin force) is relatively easy, but taming the Azure Dragon (often referring to Yang force) is by no means a matter of chance. With five Yang lines in command, the heat used in refining the elixir shifts to a fierce "martial fire" (wuhuo). At this point the Dragon and the Tiger restrain and bring each other under control.

Gradually, purple powder rises from the center of the cauldron lid. Looking inside the cauldron, one sees the elixir slowly turning the color of a red lotus. This describes continuing to apply fire and refine the elixir after the sprouts of the medicinal ingredients have been gathered. When this seasonal stage arrives, the matter that has risen to the cauldron lid is a purplish pink, while the surroundings inside the cauldron take on the hue of a red lotus.

When the allotted calamities of one's span in the world are fully exhausted, one will at last return to the old Grotto-Heaven of the Golden Altar. Once the elixir is complete, the person who takes it is bound to a term of one thousand days. Yet that person must still accumulate hidden merit in the world (yin gong, meaning secret good deeds and stored-up virtue), and only when the allotted calamities are fulfilled can they follow the elixir to its completion. The so-called "fire" refers to ascending to heaven in broad daylight or by night. If one is in a city, one may instead depart through corpse liberation (shijie). The scripture also says that the celestial immortals depart by transformation and release. At Huayang Cave there is a golden elixir altar one hundred zhang high, which is counted among the eight great Grotto-Heavens.

The Qian hexagram (the hexagram of six solid yang lines) has run through all six line positions, and the fire in the furnace blazes, filling it with red light. Practitioners of the alchemical Way liken the yang lines to the flames of the furnace fire. When Neidan (internal alchemy) reaches this stage, the Wuhuo (the "martial fire," the fiercer phase of the firing process) is at its peak, and so it is said that the blaze glows brilliantly and the whole furnace is red.

When the firing process arrives at this point, Yin-Yang is harmonized, and all the sages and perfected ones lend their joint protection. At this stage of the huandan (the process by which the internal elixir is refined), the fire has reached its extreme. The qi of the Azure Dragon is nearly spent, and the watery qi within and without has likewise been blended and exhausted, so the elixir is about to ascend into the Nine Palaces. The "noon position" here refers to the Li position in the south, which is counted as one of the Nine Palaces.

The thunder falls silent, the lightning is withdrawn, and the waters of the vast sea run dry. The Azure Dragon gives a long cry, the White Tiger lies subdued, and the tripod furnace falls empty and still. The Book of Changes says: "The overreaching dragon will have cause for regret." This means that when yang qi reaches its utmost fullness, it is called "overreaching." At this moment the Azure Dragon has been almost entirely devoured by the White Tiger, and the White Tiger has also hidden itself away. The thunder and lightning have subsided, the tripod furnace is empty and still, and there is no longer any sound or stirring of the Azure Dragon.

The master, through subtle technique, penetrates the profound principle and gathers the Yin-Yang qi together within a single chamber. When a cultivator of the elixir has refined his practice to this stage, he is able to obtain the mysterious powers that resonate with the sages, and so it is said that he has mastered the profound principle. "Gathering Yin-Yang" means drawing the Yin and Yang qi together and bringing them into harmony. Though people in the world apply their minds to seeking the great Dao, most do not understand that years, months, days, and hours each carry their own symbolism. Only by grasping the essentials of the day and the hour, and by gathering Yin-Yang, can one reach the deep principles of creation and transformation.

The Laozi Song says:

The sage seizes the essential secret of creation and transformation,

Holds the sun and moon in the palm of the hand and sets them within the furnace.

Subtly he turns the essence-qi of Heaven and Earth,

Gathers Yin-Yang, and spirits and ghosts move along with it.

The sun's hun-soul and the moon's po-soul, who can recognize them?

Whoever can recognize them is a true immortal.

Refining, nourishing, and taking the elixir for a thousand days,

If there is no yin within the body, how could one ever die?

By the time of the Gou hexagram, the practice of Neidan (internal alchemy) has gradually settled into stability. The Li Palace (the southern position in the Bagua, or Eight Trigrams, which belongs to Fire and in Neidan also refers to the site where the elixir is refined) still displays fresh auspicious signs. The cloud-and-rain imagery within the furnace and cauldron subsides and grows calm; the elixir coalesces and gives off a fragrance, presenting a scene like red blossoms in the fullness of spring.

The Gou hexagram symbolizes the first stirring of one Yin. The Yijing (Book of Changes) says, "When one treads on thin frost, one knows that solid ice is coming," meaning that Yin-qi (vital energy) has begun to gather. According to the Neidan tradition, which matches the twelve waxing-and-waning hexagrams to the yearly rise and fall of Yin and Yang, the Gou hexagram corresponds to the fifth month: after Yang-qi reaches its peak, Yin-qi begins to return. In the scripture, "light" refers to fire, and "Golden Tiger, Primordial Lord" is a symbolic title used in alchemy; "the two realms share one tally" means that Yin and Yang correspond to each other, which is why the text says "as before." What is described here is the alchemical process turning from flourishing to consolidation, as the elixir gradually forms.

The Returned Elixir (an elixir that, through cultivation, has returned to its original source) forms naturally in accordance with a certain principle; if one hoped to use this practice to seek out someone like oneself, where could such a person be found? Neidan has teachings such as "nine returns and seven reversions." What is spoken of here is the span from the eleventh month, when Yang-qi begins to return, to the fifth month, when Yang reaches its extreme and Yin is born, each stage having its own corresponding method. If one circulates the elixir's qi according to this method, those who can reach the same state are not easy to find.

Reaching the state of longevity is not easy; if one can attain this stage, one may inherit the lineage of the Three Mao Perfected Lords (figures from Daoist tradition who cultivated the Way). The scripture holds that nothing in the pursuit of long life matters more than the Great Elixir, and those who truly grasp the methods and subtle workings of this stage are rarely found. If one can cultivate to this point, one may carry on the cultivation tradition of the Three Mao Perfected Lords.

The Dun (Retreat) hexagram originally corresponds to the scenery of autumn. Now the process returns to the Kun position (the southwest in the Bagua, or Eight Trigrams, arrangement), and the fire and vapor in the furnace are drawn in accordingly. In the ordinary world, the seventh month is mid-autumn, but the alchemists call the sixth month mid-autumn, because what is meant here is the return to the Kun position, the southwest. At this time the yin lines gradually grow, and the yang lines gradually withdraw.

Next, one adds medicinals like seawater, while listening for the sound of the clepsydra (the ancient water clock) marking the hours, and visualizes the glow of red clouds spreading across the Ten Isles (the ten islands in legend where immortals dwell). There is water in the furnace, as if seawater were surging in; once it reaches the yin position, the vapor of the furnace fire is drawn in. The "mid-autumn of the sixth month" of the alchemists still refers to the return to the Kun position, the southwest, where yin lines are born and yang lines withdraw. Adding the "seawater" at this point and attending to the clepsydra's announcements serve to govern the fire phasing according to the season. When the practice of alchemy reaches this stage, one must imagine the cauldron filled with red light, like the glow of dawn clouds.

Your name is already on the register in the grotto-heaven, and you need no longer worry about the dragon and tiger in the cauldron. If one can run the alchemical method with this fire phasing, it is as though one has already been entered on the grotto-heaven's register and has the affinity to become an immortal. What is described here is that when the elixir has been refined to the point where two yin lines arise, one can avoid dispersal and error. Ordinary people do not understand the Great Dao (the Way) and devote themselves solely to embryonic breathing (a practice of refining the breath until it becomes subtle and long). Who knows that there is also a returned elixir called "Purple Wandering"? People learn only embryonic breathing and the arts of guarding with qi in the hope of long life, not realizing that embryonic breathing is merely a shallow technique that cannot transform the bones and remake a person. Ge Hong, the Immortal Master Ge, once said: "Most Daoists are foolish; they know only how to study embryonic breathing." How could they know there is the Purple Wandering elixir and the way of ascending to heaven in broad daylight?

The Pi (Obstruction) hexagram is about to arrive, exactly as one hopes: the three yang lines have withdrawn and turned back into yin. After the yellow sprout (a term in internal alchemy for the elixir or its essence) has formed, the flowers compete to bloom; after clear water is added, the seawater naturally grows deep and wide. What is meant here is that the three yang lines in the Pi hexagram have already become yin lines, and so this is called returning to yin. Once the yellow sprout has grown, one has the way of ascending to heaven in broad daylight.

The Pi hexagram (Hexagram 12 of the Yijing, or Classic of Changes) is about to arrive, and affairs will go as one wishes. The three yang lines have withdrawn and turned back into yin. Once the Yellow Sprout (a Neidan term for the medicine formed during the alchemical process) has coalesced, the elixir blossoms vie to open; as the waters keep flowing in, the sea of water within the furnace naturally deepens.

This passage means that the three yang lines of the Pi hexagram have become yin lines, which is why it speaks of "returning to yin." When the Yellow Sprout transforms into the Great Elixir, it is like flowers meeting spring, naturally bright and fragrant. When the sea of water is filled, it is deeper than before.

Within the chamber, one turns the changes of Yin-Yang as though wielding the power of creation; returning to the dusty world, one conceals one's radiance and moves with the passing times. A practitioner of Neidan (internal alchemy) employs the Qian and Kun hexagrams within a single room as if holding the transformations of heaven and earth, so that the elixir comes into being just as heaven and earth give birth to the myriad things. Once the elixir is complete, the practitioner's efficacy must in the end be revealed in the human world.

Thinking of former fellow practitioners, now long parted, one can only sigh. If there is no fated bond with them, where else is one to seek the Golden Cauldron (the alchemical furnace, also the completed elixir)? This means that those who once cultivated the elixir together were separated for a long time after being caught in war and turmoil, with no news passing between them; having lost their fated opportunity, they could not complete the Golden Elixir together.

When the Guan hexagram (Hexagram 20 of the Yijing) appears, the Dao (the Way) seems to have reached its end; the You hour (5 to 7 p.m.) falls precisely at the midpoint of the season. The You hour is regarded as an auspicious time in the elixir-cultivation formulas, occupying its proper position. The original text also says that You corresponds to the eighth month, and takes the sixth month as the midpoint of the year between heaven and earth.

If one can grasp the subtlety of the fire phasing (the mastery of timing and the progress of refining and nurturing in Neidan), one will surely complete the elixir, and the cauldron will be filled with red elixir. When the fire phasing is properly handled, the elixir will naturally form and take on its red color.

Since one has this red elixir, why worry about white hair? Dwelling in the mountains to cultivate the Dao, one can subdue the Azure Dragon (a Neidan term often used for the bodily and mental forces that must be tamed) and refine the elixir.

To immortals and to those who aspire to the Dao: although these principles have been explained, if one has still not severed the mundane mind, one cannot truly comprehend the great Dao. The fire phasing of the Golden Elixir described in the poem consists entirely of essential instructions transmitted by the immortals, and they have been set out as fully as possible. Those who are frivolous in mind and lack an affinity with the Dao will be unable to penetrate their meaning.

The Yin and Yang qi (气) circulate in turn, and by the time the Bo hexagram is reached they have gradually approached completeness. When the cultivation of the Golden Elixir (金丹) reaches this stage, one is called an immortal. What is described here is the five Yin lines receding step by step until none remain, as Yin and Yang are about to be restored to wholeness; when elixir practice attains this state, it is called immortality.

"Jade Hall" refers to the elixir chamber, and "Golden Cauldron" refers to the elixir cauldron. By the time the elixir has been refined to this point, the chamber seems to fill with fragrance of its own accord, and within the cauldron appears a vivid scene, like a red lotus that has just opened.

"Waves of the sea clarify into green water" describes the Yang fire gradually withdrawing as the Kan water flows in to replenish it, so that the breath becomes clear and still, no longer turbulent. "Setting sun" is a metaphor for the seasonal cycle of the year nearing its late phase. It also signifies that the fire phasing of the returned elixir is about to run to the end of the year, and hence the line says "floating through the passing years."

Ordinary people crave only the fame, profit, wealth, and sensual pleasures of the mortal world; how could they believe that within the mysterious art of cultivation lies a still deeper principle? The Golden Elixir moves in accord with the heavenly seasons. Taking tangible conditions of practice as its foundation and drawing its model from the "One," it is refined naturally and effortlessly.

At the Kun (坤) hexagram stage, the cultivation cycle has run its course, so the furnace fire should gradually diminish and the gentle fire (wenhuo, 文火) should likewise slow naturally. By the tenth month, all twelve stages have been completed. The fire's intensity has become faint and fine, and this is precisely the moment when pure Yin condenses, so the gentle fire must continue to be eased down.

At this point, Master Yundan (运丹先生) holds the incense tablet (xiangjian, 香简) and pays homage on the altar to the true spirits (zhenling) between Heaven and Earth, and once more petitions the constellations to protect the elixir from the intrusion of malign Qi. The practitioner must tend the furnace carefully and dare not inspect it until the fire has cooled completely; though pacing back and forth in the meantime, the mind remains fixed on the changes taking place within.

At dawn the next day, one first performs the rites of thanks, then opens the Golden Tripod (jinding, 金鼎). When opening the tripod, incense is burned and offerings are made to the true immortals of Heaven and Earth; only after the tripod has cooled may it be opened and examined. If the elixir has been successfully refined and is of superior quality, purplish-pink in color, radiant, and rising to cling above the tripod's lid, it is called the "Completion of the Purple Wandering Elixir" (zi you dan cheng, 紫游丹成).

"Gentle fire" refers to a weaker, slower degree of heat; the "incense tablet" is an incense implement used when conducting sacrificial rites; and the "Golden Tripod" refers to the tripod-furnace used in alchemical refining.