日出扶桑大海东，火轮飞渡莫松功。
鹿车搬上昆仑顶，木汞自归神室中。
扶桑红日，自西而东。正药如红日灿灿，自东而来西方。斯时也，忙驾火轮，飞渡洪涛大海，由尾闾
上夹脊双关。
纯阳曰∶子后午前定息坐，夹脊双关昆仑过。又曰∶凭君子后午前看，一脉天津在脊端。肖紫虚曰∶
几回笑指昆山路，夹脊分明有路通。但逆行道左，非鹿车不能推挽。鹿车，真意也，有这点真意，方
能逾越险阻，过得双关，上得昆仑，下得鹊桥，使活汞入于金鼎神室，而永为身宝。
艮男初归混沌窝，夫妻从此结丝罗。
六门紧闭勤添火，帐里春光要太和。
艮男喻药从艮宫而来也。混沌窝，祖气穴也。艮男之药，自东北而入祖气穴，与真铅配合，
犹夫妇结丝罗一般。然初归时，不相凝结，须紧闭六门，调息绵绵，神火薰蒸，使合为一。但合丹之火，
须文火温温，非若采取之时武火烹炼。故要太和翔洽，方能着手成春。
火记虽垂六百篇，未将真候写鸾笺。
最明莫过冲虚语，呼吸分明了却仙。
紫贤曰∶“圣人传药不传火，从来火候少人知。”金丹万卷，不笔于书，而冲虚独曰∶“火候虽云
不可传，随机默运入玄玄，达观往者千千圣，呼吸分明了却仙。”可见火候之要当于真息中求之。盖息从
心起，心静息调，息息归根，金丹之母。
然火候不一，古人以内外别之。外火候有作有为，筑基之事也。内火候则丹已得，任其自然，无为
之事也。总不离呼吸二字。不调外火候之呼吸，则不能营运此丹；不调内火候之呼吸，则不能温养此丹。故
柳华阳曰∶“凡呼吸之火，能化饮食之谷精，而助元精；凡神火能化元精而助元气；凡元气之火，能
化呼吸而助元神；元神之火，又能化形而还虚助道。成始成终，皆承火之力，以登大罗之仙。”又须知
火与候，原不相离，火必应候，候至火亦至。故火候二字，有逐节事条。不经师授，终难了彻于心，须修
德明天，以求师授。
太阳从东海扶桑升起，火候的运转如同火轮飞渡，不可松懈功夫。
像鹿车将药物搬运上昆仑山顶一样，木汞（肝魂/神气）自然回归到神室（丹田/心神居所）之中。
扶桑红日，由西向东运行。正药（先天元气）如红日灿烂，从东方来到西方。此时，急忙驾驭火轮，飞渡洪涛大海，从尾闾穴上行至夹脊双关。
纯阳子说：“子时之后、午时之前定息静坐，经过夹脊双关直达昆仑。”又说：“凭君子在子后午前观察，一脉真气津液位于脊柱顶端。”肖紫虚说：“几次笑着指向昆仑山路，夹脊分明有路相通。”但是逆行道路左侧，没有鹿车不能推挽。鹿车，指的是真意（专注的意念），有了这点真意，才能逾越险阻，通过双关，登上昆仑，下到鹊桥，使活汞（灵动的神气）进入金鼎神室，从而永远成为身体的珍宝。
艮男（指代来自艮宫的先天药物）初次回归混沌窝（祖气穴）。夫妻从此结成丝罗（阴阳结合）。
六门（眼耳鼻口等感官门户）紧闭，勤于添加火候，帐里的春光要保持太和（和谐平衡）。
艮男比喻药物从艮宫而来。混沌窝，就是祖气穴。艮男的药物，从东北方进入祖气穴，与真铅（元精/肾气）配合，就像夫妇结下丝罗一般。然而初归之时，不相凝结，必须紧闭六门，调息绵绵不断，用神火薰蒸，使二者合为一体。但是合丹的火候，必须用文火温温和和地温养，不像采取药物时用武火烹炼。所以要太和翔洽（和谐融洽），才能着手成春（成功结丹）。
虽然《火记》流传了六百篇，但没有将真正的火候写在鸾笺（信纸/书籍）上。
最明白不过的是冲虚子的话语，呼吸分明就能了却仙道。
紫贤子说：“圣人传药不传火，从来火候少人知。”金丹万卷，不记录在书上，而冲虚子唯独说：“火候虽说不可传授，但要随机默运进入玄妙境界，通达观察过往的千千圣者，呼吸分明就能了却仙道。”可见火候的要领应当在真息中寻求。因为气息从心产生，心静则息调，息息归根，这是金丹的母亲。
然而火候不止一种，古人以内外来区分。外火候是有作有为，是筑基的事情。内火候则是丹药已经得到，任凭其自然，是无为的事情。总离不开呼吸二字。不调理外火候的呼吸，就不能营运此丹；不调理内火候的呼吸，就不能温养此丹。所以柳华阳说：“凡是呼吸之火，能化饮食之谷精，而助元精；凡是神火能化元精而助元气；凡是元气之火，能化呼吸而助元神；元神之火，又能化形而还虚助道。成始成终，都承袭火的力量，以登大罗天之仙。”又须知火与候，原本不相分离，火必须应合候，候至火亦至。所以火候二字，有逐节的事条。不经师父传授，终究难以彻底领悟于心，须修养德行明晓天道，以求师父传授。
The sun rises from Fusang in the east of the sea; the operation of Huohou (Fire Timing) flies across like a fire wheel, and one must not slacken in effort.
Just as a deer cart carries the substance up to the top of Kunlun, Mugong (Wood-Mercury, referring to Liver-Hun/Spiritual Qi) naturally returns to the Shenshi (Divine Chamber, referring to Dantian/Mind Residence).
The red sun of Fusang moves from west to east. The Zhengyao (Correct Medicine, referring to Primordial Qi) shines brightly like the red sun, coming from the east to the west. At this time, one must hastily drive the fire wheel, flying across the vast ocean of waves, ascending from the Weilu point (Tailbone) through the Jiaji Double Pass.
Chunyangzi said: "Sit with regulated breath between Zi hour and Wu hour, passing through the Jiaji Double Pass to reach Kunlun." He also said: "Observe between Zi after and Wu before; a vein of Tianjin (Heavenly Saliva/Qi Fluid) is at the end of the spine." Xiao Zixu said: "Several times smilingly pointing to the road to Kunlun, there is clearly a path through the Jiaji." However, on the left side of the reverse path, without the Deer Cart, one cannot push or pull. The Deer Cart refers to Zhenyi (True Intention/Focused Will); with this True Intention, one can cross dangers, pass the Double Pass, ascend to Kunlun, descend to the Queqiao (Magpie Bridge), and allow the Huo Gong (Living Mercury/Dynamic Spirit) to enter the Jinding Shenshi (Golden Cauldron Divine Chamber), thereby becoming an eternal treasure of the body.
The Gen Nan (Gen Male, metaphor for the medicine originating from the Gen Palace) first returns to the Hundun Wo (Chaos Nest, i.e., Zuqi Acupoint). The husband and wife thus tie their silk ropes (Yin-Yang union).
Keep the Six Gates (sensory openings such as eyes, ears, nose, mouth) tightly closed and diligently add fire; the spring light within the tent must maintain Taihe (Great Harmony).
Gen Nan metaphorically represents the medicine coming from the Gen Palace. Hundun Wo is the Zuqi Acupoint. The medicine of Gen Nan enters the Zuqi Acupoint from the northeast and combines with Zhenqian (True Lead, referring to Yuanjing/Kidney Qi), much like a husband and wife tying their silk ropes. However, upon initial return, they do not yet condense; one must tightly close the Six Gates, regulate breath continuously, and use Shenhuo (Spirit Fire) to fumigate, causing them to merge into one. Yet, the Huohou for combining the Dan must be Wenhuo (Civil/Gentle Fire), warm and mild, unlike the Wuhuo (Martial/Intense Fire) used during Caiqu (Collection). Therefore, one must achieve Taihe Xiangqia (Harmonious Integration) to successfully initiate the process (Zhaoshou Chengchun).
Although the *Huoji* (Records of Fire) has been handed down in six hundred chapters, it has not written the true Houhou (Timing of Fire) on Luanjian (ornate paper/books).
Nothing is clearer than the words of Chongxu: "Clear breathing allows one to complete the Immortal Dao."
Zixianzi said: "Sages transmit the medicine but not the fire; since ancient times, few have known the Huohou." Ten thousand volumes of Golden Dan are not recorded in books, yet Chongxu alone said: "Though Huohou is said to be untransmittable, one must silently operate according to circumstances to enter the profound mystery. Observing past sages by the thousands, clear breathing allows one to complete the Immortal Dao." This shows that the essence of Huohou should be sought in Zhenxi (True Breath). For breath arises from the Heart; when the Heart is still, breath is regulated; breath returns to its root with each cycle; this is the mother of Golden Dan.
However, Huohou is not uniform; ancients distinguished it as internal and external. External Huohou involves action and doing, pertaining to the foundation-building stage. Internal Huohou occurs when the Dan is already obtained, allowing nature to take its course, pertaining to non-action. It fundamentally revolves around the two characters of breathing. If one does not regulate the breathing of external Huohou, one cannot circulate this Dan; if one does not regulate the breathing of internal Huohou, one cannot warm-nourish this Dan. Thus, Liu Hanyang said: "All breathing-fire can transform the grain essence of food and assist Yuanjing; all Spirit-fire can transform Yuanjing and assist Yuanqi; all Yuanqi-fire can transform breathing and assist Yuanshen; Yuanshen-fire can further transform form and return to emptiness to assist the Dao. From beginning to end, all rely on the power of fire to ascend to the Luotian Immortal realm." One must also know that Huo (Fire) and Hou (Timing) are inseparable; Fire must correspond to Timing, and when Timing arrives, Fire also arrives. Therefore, the term Huohou consists of detailed items step by step. Without transmission from a master, it remains difficult to thoroughly understand in the heart; one must cultivate virtue and illuminate the Way to seek a master's instruction.