大般涅槃經義記 8.202

8.202

第四辯定我無我中，初明佛性實非是我，為生說我。問曰：上來數說佛性是其真我，今以何故說實非我？釋言：佛性備含多義，亦有我義及無我義，亦有非我義，但向為彼我見外道愛喜我故偏說為我。雖為說我，恐畏同彼先所建立，故復拂遣，明實非我。此說非我，亦是化耳。「有因緣」下明雖異說而非虛妄。於中通對佛我顯之，句別有四：一明如來無我說我而非虛妄。二明如來說我為無我而非虛妄。隨化說此，故曰有緣。三辯初句佛性無我、如來說我，佛性未有八自在用，故名無我。四辯第二如來是我、佛說無我，如來具有八自在用，故名為我。上來正說我為佛性。

In the fourth point, definitively distinguishing self and non-self, it first explains that the buddha-nature is truly not the self, but for the sake of sentient beings he speaks of the self. Question: Above, it repeatedly stated that the buddha-nature is the true self; why does it now say that it is truly not the self? Explanation: The buddha-nature fully contains many meanings; it also has the meaning of self and the meaning of non-self, as well as the meaning of neither self [nor non-self]. But previously, for the sake of those non-Buddhists attached to the view of self who relish the self, he exclusively spoke of it as the self. Although he spoke of the self for their sake, fearing that it would be equated with what they had previously established, he sweeps it away again, clarifying that it is truly not the self. This statement of non-self is also merely a teaching of transformation. From "There are causes and conditions..." downward, it explains that although these are different teachings, they are not false. Therein, it reveals them broadly in contrast between the Buddha and the self, in four distinct clauses: first, it explains that for the Tathāgata, non-self being taught as self is not false; second, it explains that for the Tathāgata, self being taught as non-self is not false. Since these are taught in accordance with transformation, it says there are conditions. Third, it distinguishes the first clause, where the buddha-nature is non-self and the Tathāgata speaks of self: because the buddha-nature does not yet possess the eight sovereign functions, it is called non-self. Fourth, it distinguishes the second clause, where the Tathāgata is the self and the Buddha speaks of non-self: because the Tathāgata fully possesses the eight sovereign functions, he is called the self. The above directly explains the self as the buddha-nature.