肇論新疏 2.198

2.198

大權利物是唯無感，感之必應，信若四時也。直者，正也。虛無者，語借老氏，謂般若之體妙湛絕相曰虛，永盡惑取曰無。斯不下，結成。賢首大師云：「非生非滅，四相之所不遷。」謂既以至虛為性，則感來非生、感謝非滅，故云不可得等。

The great expedient means benefits beings only when there is no stimulus; when stimulated, it unfailingly responds, as trustworthy as the four seasons. "Directly" means uprightly. "Vacuous non-being" borrows words from Laozi: prajñā's substance is wonderfully serene and transcends marks, which is called "vacuous"; it eternally exhausts delusion and grasping, which is called "non-being." From "This can neither" onward, he concludes. Great Master Xianshou says: "Neither arising nor ceasing, it is not altered by the four characteristics." This means that since it takes utmost vacuity as its nature, its coming upon stimulus is not arising, and its fading upon stimulus is not ceasing; hence he says, "can neither be made," and so forth.