Daoism Series 15: 不死方 The Formula of the Undying

The term of the Formula of the Undying [bu si fang不死方] appears in the《Rhymed Formula of the Reverted Elixir》[huan dan ge jue 还丹歌诀] by Yuan Yang Zi [元阳子] during the Five Dynasties Period (907-960).

长生药，不死丹，世人欲作寻复难。心犹豫，意迟疑，八丹方法由来有，如何不取一 门知。二人语， 共商量，日夜寻思不死方。若取黑铅并奼女，腾身天上自翱翔。一为左，一为右，阴阳具足还丹就。 真须炼，必长生，逍遥自在紫雲庭。

The medicine for long life, ‘the Elixir of the Undying’, which the common people desire to fabricate, is difficult to seek and duplicate. With the Heart-Mind being irresolute, the mind being hesitant, and the method of the Eightfold Elixir’s origin being extant, how could one not select the knowledge of the one Gate? The men converse and discuss together, day and night pondering over and seeking the Formula of the Undying. If [one simply] picks out black lead to combine together with the beautiful lady, then one’s body gallops to the Heavens where it soars by itself. If Yin and Yang are completely sufficient – one left and one right – that is Reverting to the Elixir. If one truly awaits until this is tempered and refined, there will certainly be long-lasting life, and one will be free, footloose and unfettered in the Purple Cloud Court.

Furthermore, the Buddhist《Golden Light Scripture》[jin guang ming jing 金光明经] states:

甘露是诸天不死之药，食者命长身安，力大体光。
The sweet dew is the medicine of undying for all the Heavens. When ingested, the Life-Destiny becomes long-lasting and the body safeguarded, [and one’s] powers will be great and [one’s] body radiant.

Last but not least, there is also an important reference to this concept in the《Vimalakirti Nirdesa Sutra》[zhu wei mo jing注维摩经] from the 1st-2nd century:

诸天以种种名药，著海中，以宝山摩之，令成甘露。食之得仙，名不死药。
All the Heavens place many kinds of famous medicines within the ocean, and employ treasured mountains to grind [them], to make them turn into Sweet Dew. [When] ingested, [one] will attain immortality; its name is the Medicine of the Undying.

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Post-Scriptum: This is one of the entries of the appendix of the 49 Barriers of Daoist Cultivation by XIng De (Li Shi Fu) which did not make it into the final version due to the book becoming to voluminous.