大般涅槃經疏 1.23

1.23

我聞者，我我、我無我、無我我、非我非無我。聞聞、聞不聞、不聞聞、不聞不聞。三種我聞是昔所聞方便之義；非我非無我、不聞不聞圓論我聞者，今經正意。

'I have heard': the self of self, the self of non-self, the non-self of self, and neither self nor non-self. Hearing hearing, hearing non-hearing, non-hearing hearing, and neither hearing nor non-hearing. The three kinds of 'I have heard' are the meanings of skillful means heard formerly; the perfect discussion of 'I have heard' as neither self nor non-self, and neither hearing nor non-hearing, is the correct intention of the present sūtra.