Bhagavad Gita As It Is - Chapter 8 verse 20

paras tasmāt tu bhāvo 'nyo
'vyakto 'vyaktāt sanātanaḥ
yaḥ sa sarveṣu bhūteṣu
naśyatsu na vinaśyati

paraḥ—transcendental; tasmāt—from that; tu—but; bhāvaḥ—nature; anyaḥ—another; avyaktaḥ—unmanifest; avyaktāt—from the unmanifest; sanātanaḥ—eternal; yaḥ—that; saḥ—which; sarveṣu—all; bhūteṣu—manifestation; naśyatsu—being annihilated; na—never; vinaśyati—annihilated.

TRANSLATION
Yet there is another nature, which is eternal and is transcendental to this manifested and unmanifested matter. It is supreme and is never annihilated. When all in this world is annihilated, that part remains as it is.

PURPORT
Kṛṣṇa's superior spiritual energy is transcendental and eternal. It is beyond all the changes of material nature, which is manifest and annihilated during the days and nights of Brahmā. Kṛṣṇa's superior energy is completely opposite in quality to material nature. Superior and inferior nature are explained in the Seventh Chapter.