I heard these words of the Buddha one time when the Lord was residing at Shravasti with his community of bhikshus. One day, he told the community, “Do you know of the wonderful Dharma Seal? Today I would like to tell you about it and explain it to you. Please use your pure mind to listen and receive it with care, and make the best effort to remember and practice it.” The community of bhikshus replied, “Wonderful, World-Honored One! Please teach us. We will listen carefully.”
The Buddha said, “Emptiness is neither being nor nonbeing. It is free from all wrong views. It is neither produced nor destroyed, and it cannot be grasped by views. Why is this so? Because emptiness cannot be located in space. It has no form. It is not an object of perception. It has never been born, and the intellect cannot grasp it. Because it cannot be grasped, it embraces all dharmas and dwells only in non-discursive, nondiscriminative wisdom. This is the true and right understanding, bhikshus! You should know that not only emptiness, but all dharmas are like that. This is the Dharma Seal.
“The Dharma Seal is also called the Three Doors of Liberation. It is the basic teaching of all Buddhas, the eye of all Buddhas, the destination of all Buddhas. Listen and receive it with care. Memorize it well in order to reflect and look deeply into it right in the heart of reality.
“Bhikshus, find a quiet place to meditate, such as in a forest under a tree. There you can see that form is impermanent, subject to change, unstable and empty, and as a result, you will not be attached to form. You will reach the nondiscriminative understanding of form. Then do the same for feelings, perceptions, mental formations, and consciousnesses. See that they are impermanent, subject to change, unstable and empty, and rise above wrong views about them. Realize the nondiscriminative understanding of feelings, perceptions, mental formations, and consciousness. Bhikshus, the Five Aggregates are empty. They are produced from the mind. Once the mind stops operating in its usual way, the aggregates stop operating as well. When you see this, you will be liberated, free from all views. This is emptiness, the First Door of Liberation.
“Bhikshus, dwelling in concentration, see the dissolution of form, and be free from the illusory nature of perception vis-à-vis form. See the dissolution of sound, smell, taste, touch, and objects of mind , and be free from the illusory nature of perceptions vis-à-vis sound, smell, taste, touch, and objects of mind. This meditation is called signlessness, the Second Door of Liberation. Once you have entered this door, your knowledge will be pure. Because of this purity of understanding, the three defiling qualities of mind—greed, hatred, and delusion—will be uprooted. With these uprooted, you will dwell in the realm of nondiscursive, nondiscriminative knowledge. When you are dwelling in this knowledge, views concerning ‘me and mine,’ and thus all views, no longer have the bases and the occasions to arise.
“Bhikshus, once you are free from the view ‘I am,’ you no longer consider what you see, hear, feel, and perceive as realities independent of your own consciousness. Why? Because you know that consciousness also arises from conditions and is impermanent. Because of its impermanent nature, it cannot be grasped either. This meditation is called wishlessness, the Third Door of Liberation. Once you enter this door, you experience fully the true nature of all dharmas, and you no longer cling to any dharma because you have seen the unconditioned nature of all dharmas.”
The Buddha told the community of bhikshus, “This is the wonderful Seal of the Dharma, the Three Doors of Liberation. If you learn and practice it, you will certainly attain pure insight.”
The monks were very happy to hear the teaching of the World-Honored One. They paid respect to him and promised to learn and practice this wonderful teaching.
Translated by Thich Nhat Hanh from the Chinese: Taishō Revised Tripiṭaka 104. Related: Samyukta Āgama 80.