Twofold entrance to Tao

“There are many ways to enter the Path, but briefly speaking they are of two sorts only. The one is "Entrance by Reason" and the other "Entrance by Conduct"

By "Entrance by Reason" we mean the realization of the spirit of Buddhism by the aid of the scriptural teaching. We then come to have a deep faith in the True Nature which is the same in all sentient beings. The reason why it does not manifest itself is due to the over wrapping of external objects and false thoughts. When a man, abandoning the false and embracing the true, in singleness of thought practises the Pi-kuan [Wall-gazing] he finds that there is neither self nor other, that the masses and the worthies are of one essence, and he firmly holds on to this belief and never moves away there from. He will not then be a slave to words, for he is in silent communion with the Reason itself, free from conceptual discrimination; he is serene and not-acting. This is called "Entrance by Reason".

By "Entrance by Conduct" is meant the four acts in which all other acts are included. What are the four? 1. To know how to requite hatred; 2. To be obedient to karma; 3. Not to crave anything; and 4. To be in accord with the Dharma.”
(Bodhidharma on the twofold entrance to the Tao [D T Suzuki] sacred-texts.com)

Upon birth, people fall from the Tao, and human nature (Hsing) separates from life (Ming). All the great masters including Bodhidharma (who spent nine years wall-gazing inside a cave in China) and Daoist immortals realize this separation therefore they teach the same path (in their respective ways) to return to the Tao that is to cultivate essence (hsing) and bodily life (ming). The “Not Two” in the Hsin Hsin Ming may just have this meaning. Only when the two becomes one again can a Buddhist become a Buddha and a Daoist become an Immortal.

If we read and ponder the books, texts, and classics of the Three Doctrines (Buddhist, Confucian, Daoist), the great masters’ thoughts on how to cultivate essence and bodily life are contained therein. How far we can learn, practise and reach will depend on our own sincerity.