The four sentences realized by Bodhidharma when facing the wall are: externally breathing all conditions, internally breathless, and the heart is like a wall, you can enter the Tao.

Master Bodhidharma is the founder of Chinese Zen, and the foundation not only established a sect, but also must have his own ideological purpose and practice method as the difference between this sect and another sect. Master Bodhidharma has a French article that specifically explains the method of entering Zen, which is "A brief analysis of the four elements of the Mahayana", also called "A brief analysis of the four elements of the Mahayana" and "A brief analysis of the four elements of the Mahayana".

The Zen practice method he teaches is "two entrances and four elements". The "two entrances" are the entrance of principles and the entrance of practice, and the "four conducts" are the conduct of repaying grievances, the conduct of following circumstances, the conduct of seeking nothing, and the conduct of advocating Dharma. This is the basic content of Master Bodhidharma's Zen method.

Related information:

The so-called "Those who feel at ease just sit back and watch." Patriarch Bodhidharma spent nine years in Mount Song facing the wall. His method of peace of mind is facing the wall. The second mantra is called "This is how it is issued", "This is how it is issued". The third mantra is called "This is how things go well with things", "Those who go well with things like this are protected from ridicule". The fourth sentence is "It's so convenient", "It's so convenient that you can't get rid of it".

I feel that these four sentences are very important. They are not only the true biography of Master Bodhidharma, but also the source of all Zen methods in Zen since Bodhidharma. When Master Tan Lin wrote this preface, he believed that this was the true way taught by Master Bodhidharma, and the real way consisted of these four sentences. We can briefly analyze how Master Bodhidharma taught us to enter Zen from these four sentences.

First of all, "Those who feel at ease like this just sit back and watch." In the Tang Dynasty, Zen Master Guifeng Zongmi's "Preface to the Collection of Zen Sources" summarized Bodhidharma's Zen method and said: "Teaching people to feel at ease by watching on the wall."

Wall view includes four points: "Externally, all conditions are breathed, and there is no breath in the heart. The heart is like a wall, and you can enter the Tao." If we want to feel at ease, we must make the heart become a wall. This wall is not an earth wall or a mud wall, but a copper wall and an iron wall. Even flies and mosquitoes cannot get in, and no bacteria can corrode it. This is called a heart like a wall. This mind must be protected like a wall so that no delusions of worldly labor or worldly material desires can erode in.