Chapter 227 The Evil Approach In Cultivation

The higher-grade alchemy uses God as the furnace, sex as medicine, concentration as fire, and wisdom as water. The middle-grade alchemy uses God as the furnace, qi as medicine, the sun as fire, and the moon as water. The lower-grade alchemy uses the body as the furnace, qi as medicine, the heart as fire, and the kidney as water.
This was a Taoist life nurturing ideology derived from "Huang Lao Lie Zhuang", which was a way of practicing life.
Most of the righteous sects pursued self-cultivation by refining essence into qi, refining qi into spirit, refining spirit and returning to emptiness, then spirit into union with Tao.