六祖大師法寶壇經 1.67

1.67

師示眾云：「善知識！我此法門，以定慧為本。大眾！勿迷，言定慧別。定慧一體，不是二。定是慧體，慧是定用。即慧之時定在慧，即定之時慧在定。若識此義，即是定慧等學。諸學道人，莫言先定發慧、先慧發定各別。作此見者，法有二相。口說善語，心中不善。空有定慧，定慧不等。若心口俱善、內外一如，定慧即等。自悟修行，不在於諍。若諍先後，即同迷人，不斷勝負，却增我法，不離四相。善知識！定慧猶如何等？猶如燈光。有燈即光，無燈即闇。燈是光之體，光是燈之用；名雖有二，體本同一。此定慧法，亦復如是。」

The Master instructed the assembly, saying: "Good friends! This Dharma gate of mine takes samādhi and prajñā as its basis. Great assembly! Do not be deluded and say that samādhi and prajñā are different. Samādhi and prajñā are of one substance, not two. Samādhi is the substance of prajñā; prajñā is the function of samādhi. At the very moment of prajñā, samādhi is within prajñā; at the very moment of samādhi, prajñā is within samādhi. If you understand this principle, this is the equal study of samādhi and prajñā. Practitioners of the Way, do not say that first samādhi gives rise to prajñā, or first prajñā gives rise to samādhi, as if they were separate. For those who hold this view, dharmas have two characteristics. Mouth speaking good words, inside the mind not being good: in vain they have samādhi and prajñā, but samādhi and prajñā are not equal. If mind and mouth are both good, and inside and outside are as one, then samādhi and prajñā are equal. Self-awakening and cultivation do not lie in disputing. If you dispute precedence, you are like deluded people; not severing victory and defeat, you instead augment [attachments to] self and dharmas, and do not leave behind the four characteristics. Good friends! What are samādhi and prajñā like? They are like a lamp and its light. Where there is a lamp, there is light; where there is no lamp, there is darkness. The lamp is the substance of the light; the light is the function of the lamp. Though the names are two, their substance is fundamentally one. This Dharma of samādhi and prajñā is also like this."