Therefore you have only to make the light circulate: that is the deepest and most wonderful secret. The light is easy to move, but difficult to fix. If it is made to circulate long enough, then it crystallizes itself; that is the natural spirit-body. This crystallized spirit is formed beyond the nine heavens. It is the condition of which it is said in the Book of the Seal of the Heart: "Silently thou fliest upward in the morning".
Translators of The Secret of the Golden Flower are Richard Wilhelm and Cary F. Baynes. If you missed any posts in this series, please utilize the Golden Flower label below.