Diamond Sutra 經剛經：須菩提，所謂佛法者，即非佛法。

經剛經：須菩提，所謂佛法者，即非佛法。
"Subhūti, that which is called the buddhadharma is not the buddhadharma."

金剛般若波羅密經講義：
Commentary:

佛恐初發心菩薩，因聞佛與法，皆是從此經出，又執著於有，故立即告訴須菩提：「所謂佛法者，即非佛法」。意思是說：雖然一切諸佛因中修行，皆能離相無住，與實相般若相應，而證得阿耨多羅三藐三菩提；但諸佛心中并不認為有佛道可成，有菩提法可得。如圓覺經言：「一切如來圓覺妙心，本無菩提及與涅槃，亦無成佛及不成佛，無妄輪迴，及非輪迴。」不過，在世俗諦因緣的名相上說：是佛法而己。若依真諦理言：則諸佛所證的菩提法，己經遠離諸相，不可取，不可說，不應執著。若然執著有佛可成，有法可得，己經「即非」真正的「佛法」了，

The Buddha feared that those who had just resolved to be bodhisattvas (Buddhists), and who had heard that all the Buddha and his dharma could be found in this sutra, would also cling to this sutra; so he immeidately told Subhūti, "that which is called the buddhadharma is not the buddhadharma." This is to say: although all the Buddhas during their practice can leave behind forms, realize perfect knowledge, and realize correct universal intelligence, they still know in their heart that there is no Buddhist path to accomplish, now knowledge to be obtained. It is as the Perfect Enlightenment Sutra states: "All true enlightenment and the most wonderful of hearts, know that there is no bodhi or nirvana, there is no becoming a Buddha or not becoming a Buddha, no unreal reincarnation and no real reincarnation. However, in common understanding cause and effect has a form and it says: this is only buddhadharma. (In other words,) if we speak in line with the reasoning of the noble truths: the perfect knowledge, proven by the buddhadharma, is already very distant from all forms, it is unattainable, unspekable, and should not be grasped at. If one grasps at a Buddha to become, or at a dharma or doctrine that could be attained, then this "is not" the true "buddhadharma."

佛先說法施福勝，能出生諸佛，以遣空；又說佛法非佛法，以遣有。目的是令眾生知道，在世諦因緣說：是有凡有聖，有迷有悟，有因有果，有修有證；豈可撥無因果而墮於空？但在真諦理言：諸法自性清淨，本無一物，何來聖凡迷悟染淨因果諸法？豈可著相而執有？如是空有二俱非，真俗圓融，始可以會歸中道。是以下文每以即非、是名等詞句，顯般若三諦圓融之理。

The Buddha first says that practicing the dharma will bring prosperity and improvement, that one can leave life and become a Buddha, in order to drive away (the thought of) emptiness; he then says the the buddhadharma is not the buddhadharma, in order to drive away (the thought of) existence. The goal is to cause people to understand that in the concept of cause and effect in ordinary or worldly truth says: there is the common and the holy, the confused and the enlightened, a cause and an effect, practice and revelation; can one throw away the idea of cause and effect and fall into (the idea of) emptiness? But the categories of (true) reality state: All dharmas are by nature pure; originally no one thing existed; from where could the holy and the common, confusion or enlightenment, contamination or purity, cause and effect come from? Is there really a form to grasp at? And in this way emptiness denies two different things, the absolute and relative truth are resolved, and one can finally begin to follow the middle path. This use of negating different things in the passages below such as "this name," make obvious the logic of the unity of the three doctrines.*

須菩提白佛言：世尊！佛得阿耨多羅三藐三菩提，為無所得耶？佛言：如是！如是！須菩提！我於阿耨多羅三藐三菩提，乃至無有少法可得，是名阿耨多羅三藐三菩提。

Subhūti said to the Buddha: "World Honored One. When the buddhas attain peerless perfect enlightenment, is it the case that actually nothing is attained?"

"Exactly right. Subhūti, as far as peerless perfect enlightenment is concerned, I have not attained the slightest thing. This is why it is called peerless perfect enlightenment."

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English of Diamond Sutra translated by A.C. Muller; commentary (written by Rev. Sik, Man Chu) translated by me.

* To quote Soothill, the three dhogmas can be explained thus: "三諦 The three dogmas (空假中). ... (a) by 空 śūnya is meant that things causally produced are in their essential nature unreal (or immaterial) 實空無; (b) 假, though things are unreal in their essential nature their derived forms are real; (c) 中; but both are one, being of the one 如 reality.