大乘起信論義記 2.28

2.28

言心性不生滅者，釋上法體，謂隨妄不生、約治不滅，又修起不生、處染不滅，故《攝論》云「世間不破，出世間不盡」故也。

"The nature of the mind is unarising and unceasing" explains the Dharma-essence above: it means that following the false it does not arise, and in terms of remedy it does not cease; furthermore, cultivated and aroused it does not arise, and dwelling in defilement it does not cease. Hence the Mahāyānasaṃgraha says: "The worldly is not destroyed, and the supramundane is not exhausted."