諸真聖胎神用訣/Zhuzhen Shengtai Shen Yong Jue – Various Genuine Holy Embryo Spirit Application Secrets, Number 4

又曰：形中子母，何不守之？且形中以元炁為母，以神為子，初因呼吸之炁而立成形，故為母也。形炁既立，而固有神，故為子也。夫至神也，與炁合形，神與炁但循環於臟腑之內，馭呼吸於上下，久久習之，則神自明，而炁自和。神既內明，照徹五藏，炁和則使用於四肢。故黃帝三月內視，住心以神，則化生纏綿五藏。斯言可推而得之也!

It is also said: “The Form contains a Child & Mother, why not protect them? Moreover, within the Form, the Original Qi is the Mother, the Spirit is the Child. The Qi of breathing is the initial reason that causes the establishment of the developing Form, therefore it is the Mother.  Once the Qi of the Form has been established, the Spirit inherently exists, therefore it is the Child. Thus arriving at Spirit, & with Qi joining the Form, Spirit & Qi will circulate Internally in the Organs & Viscera. By managing the Breathing both Above & Below, & practicing it for a very long time, then the Spirit will naturally be bright & the Qi wil naturally condense. Once the Spirit is already internally bright, its illumination will pervade the Five Organs. When the Qi is condensed then it can be used in the Four Limbs. Therefore, Huangdi’s Three Months of Inner Observation, Dwell in the Xin & Use the Spirit, is able to transform the birth of the emotions lingering around the Five Organs. These words are able to advance & obtain it!”