Linji (or Lin-Chi or in Japanese Rinzai Gigen) is one of the outstanding proponents of the Ch'an tradition from China. Ch'an, which later traveled to Japan and became known there as Zen, is a synthesis of Buddhist and Taoist teachings.
In "The Golden Age Of Zen: Zen Masters of the T'ang Dynasty" John Wu writes:
Linji saw in each and every one of his students the “aboriginal Self ” waiting with patient eagerness for any opportunity to break through the shell of the little ego, so that, released himself, he could have a free hand in releasing the ego from its self-imposed bounds of ignorance and craving. Yet, what a pathetic sight it must have been for Linji to see that most of his pupils, impervious to their original free-born state, seemed to be willing to remain snugly in slavery. Turning their back upon Intuition, they would rather pay tuition for worthless “ tuitions.” Carrying within them the very “ Mother of Buddha, ” they turned their eyes outwards to seek an external Buddha. Why should these seekers, Lin - chi often wondered, have left their households, only to belong to another household? Underneath all his roughness there was a burning compassion, which was all the more inevitable because it was not blind but enlightened. In this light, we can easily see that all his shouts and beatings actually sprang from the fountain of his compassionate heart.
Frequent as was his resort to the rod, Linji had nevertheless been noted in later generations as the master of shouts, as is evident in the well - known saying: “ Te-shan’s beatings, Linji’s shouts. ”It is not without reason that he has been considered a specialist in shouting, seeing that he developed a philosophy of shouting. He classified shouts into four main categories. As he once expounded to a monk, “Sometimes, a shout is like the sword of the vajra - king; sometimes, a shout is like a lion crouching on the ground; sometimes, a shout is like a sounding rod for testing the grasses; sometimes, a shout is not used as a shout. ” After stating these categories, he asked the monk, “ How do you understand this? ” As the monk was fumbling for an answer, the master shouted. I suppose that this shout belongs to the first category, because it was meant to cut off the monk’s chain of thoughts which would lead nowhere.
The true follower of Tao does not grasp at the Buddha, nor at Bodhisattvas, nor at the Arhats, nor at the exceeding glories in the three realms. In his transcendental independence and untrammeled freedom, he adheres to nothing. Even if the universe should collapse, his faith would not falter. Should all the Buddhas from the ten heavens appear before him, he would not feel the slightest elation. Nor would he experience the slightest fear, should all the demons come out from the three hells. How can he be so calm? Because he sees the fundamental voidness of all things, which are real only to those still subject to change but not to the immutable. The three realms are only a manifestation of the mind, and the ten thousand things arise from consciousness. What then is the use of grasping at a dream, an illusion, a flower in the air? Only the one person who is right now before your very eyes listening to my discourse, is authentically real. He can enter into fire without being burned, and plunge into water without being drowned. The three hells would be turned into a pleasure garden for him. Ministering unto the hungry ghosts and beasts, he accepts no reward. What makes such a state possible? The Law of Non - discrimination! If you should love the saintly but hate the worldly, you will never cease to be engulfed in the sea of birth and death. Afflictions and trials ( klesha ) exist because you are mindful of them. But if you are not mindful of them, how can they disturb you? Spare yourself the vain labor of discriminating and grasping at appearances and in a single instant you will realize Tao with spontaneous ease.
(quoted from "The Golden Age Of Zen: Zen Masters of the T'ang Dynasty")