仁王般若經疏 2.126

2.126

大王如如文字下，答問中第二，明三種佛性：初現常佛性、二當常佛性、三了因佛性。佛性非當現，而約緣當現不同，故有三種之說。若無依無得隨緣說者，無過；若執當現是定實者，即成諍論。初現常，文言如如文字修諸佛智母一切眾生性根本智母即為薩婆若體者，以前聞十二部經如，故知文字即是如。如即是波若，波若為佛母，故云智母。言一切眾生性根本智母者，知眾生性不可得即如，故云即為薩婆若體。達解眾生與薩婆若不一不二，何當何現？破當故說現耳。諸佛未成佛下，第二明當果佛性。何以得知？文云諸佛未成佛，當佛以為智母，未得為性。故知當有非現有。現有者有隱性，當無者無當性，故知顯故名當、隱故名現。論其實性，體絕諸非。當非現，現以因緣，故說當說現耳。已得下，第三明了因佛性。明三乘波若了出不生不滅，以得波若正觀體知生者不生、滅者不滅，故云自性常住。一切眾生虛妄因緣輪迴六趣，體知虛妄無從，即是不生不滅，故云以此自性常住為覺性也。

From "Great King! Just as the thusness of written words..." down is the second part of the reply to the question, clarifying three kinds of buddha-nature: first, the presently eternal buddha-nature; second, the future eternal buddha-nature; third, the revealing-cause buddha-nature. Buddha-nature is neither future nor present, yet because it varies according to conditions as future or present, there is the explanation of three kinds. If one speaks in accordance with conditions without reliance and without acquisition, there is no fault; but if one clings to future and present as fixed and real, it leads to disputation. As for the first, the presently eternal, the text says: "Just as the thusness of written words cultivates the mother of the wisdom of all buddhas, the root mother of wisdom of the nature of all sentient beings is precisely the substance of sarvajñā": because one previously heard that the twelve divisions of the canon are thusness, one knows that written words are precisely thusness. Thusness is precisely prajñā, and prajñā is the mother of the buddhas; hence it is called "mother of wisdom." Saying "the root mother of wisdom of the nature of all sentient beings" means that knowing that the nature of sentient beings is ungraspable is precisely thusness; hence it says "is precisely the substance of sarvajñā." If one comprehends that sentient beings and sarvajñā are neither one nor two, what is future and what is present? The present is spoken of merely to refute the future. From "Before all buddhas have attained buddhahood..." down, the second part clarifies the future-fruit buddha-nature. How is this known? The text says: "Before all buddhas have attained buddhahood, they take the future buddha as the mother of wisdom, not having yet attained it as their nature." Hence one knows that there is the future, not the present. "Present existence" is possessing the hidden nature; "future non-existence" is lacking the future nature. Hence one knows that because it is manifested it is called future, and because it is hidden it is called present. To discuss its true nature, its substance transcends all negations. The future is not the present; the present is through causal conditions; hence the future and the present are spoken of. From "having already attained..." down, the third part clarifies the revealing-cause buddha-nature. It clarifies that the prajñā of the three vehicles reveals the unproduced and unextinguished: because one attains the correct contemplation of prajñā, one personally realizes that what is produced is unproduced, and what is extinguished is unextinguished; hence it says "its self-nature is eternally abiding." All sentient beings transmigrate in the six destinies through false causal conditions; personally realizing that falsehood has no origin is precisely the unproduced and unextinguished; hence it says that they "take this eternally abiding self-nature as their awakening nature."