楞伽阿跋多羅寶經註解 1.605

1.605

我常不思議等者，佛謂我之所得不思議以自證為因相，不同外道有已還無為無常、以神我思量計常。若復外性等者，復斥外計亦有四義：初斥思量計常、二名不知常不思議自因之相、三斥去佛所得相遠、四彼不應說者斥其但有言說也。

'My permanence and incomprehensibility' and so forth: the Buddha says that the incomprehensibility attained by me takes self-realisation as its causal lakṣaṇa, unlike the tīrthikas who take having existed and reverting to nonexistence as impermanence, and use a spiritual self to mentally deliberate and construct permanence. 'If there are further external beings' and so forth again refutes the external constructions, also with four meanings: first, refuting mentally deliberating and constructing permanence; second, termed not knowing the lakṣaṇa of the intrinsic cause of permanence and incomprehensibility; third, refuting being far removed from the lakṣaṇa attained by the Buddha; fourth, 'they should not speak [of it]' refutes their possessing mere verbal expressions.