fire phases; fire times
A name of the main practice performed in the first stage of the Nanzong (Southern Lineage) codification of Neidan and in other varieties of Neidan. Fire—whose function in Neidan is performed by Spirit (shen)—is progressively increased when the Essence (jing) first rises through the Three Barriers (sanguan) in the back of the body to the upper Cinnabar Field (niwan), and then progressively decreased when the Essence descends through the three Cinnabar Fields (dantian) in the front of the body to the lower Cinnabar Field. The twelve stages of the sequence are represented by the twelve sovereign hexagrams (bigua), the twelve earthly branches (dizhi), and the twelve pitch-pipes (zhonglü). See the table below.
The twelve “sovereign hexagrams” (bigua)
and their relation to other duodenary series:
earthly branches (dizhi), bells and pitch-pipes
(zhonglü), months of the year,
and “double hours” (shi).
⊛ A blazing fire grows below: by day and by night its sound is unchanging and steady. . . . It will rotate through twelve nodes, and when the nodes are complete, it will again need your care. 炎火張於下，晝夜聲正勤。. . . 周旋十二節，節盡更須親。 (The Seal of the Unity of the Three, sec. 40)
⊛ Even if you discern the Vermilion Cinnabar and the Black Lead, it will be useless if you do not know the Fire phases. 縱識朱砂與黑鉛，不知火候也如閑。 Comm. Liu Yiming: The formation of the Golden Elixir entirely depends on the practice of the Fire phases. “Fire” means the force of the practice; “phases” means the sequence of the practice. When you collect the Medicine, you must know what comes first and what comes after; when you refine the Medicine, you must know the time segments. 金丹全賴火候修持而成。火者修持之功力，候者修持之次序，採藥須知遲早，煉藥須知時節。 (Awakening to Reality, "Cut-off Lines", poem 27, trans. in Taoist Internal Alchemy: An Anthology of Neidan Texts, p. 81)
⊛ In the alchemical texts, Fire is a metaphor of Original Spirit. When Original Spirit coalesces with Essence and Breath, they circulate along the path of the Function and Control vessels (renmai and dumai). The operation of heating them as they begin to circulate is called Fire phases. The word “phases” (hou) means “stages”, and refers to the stages of advancement and withdrawal, slow and fast pace, and ascent and descent in the circulation of the External Medicine (waiyao). (Wang Mu, Foundations of Internal Alchemy, p. 74)