BG 8.18

अव्यक्ताद्व्यक्तयः सर्वाः प्रभवन्त्यहरागमे। रात्र्यागमे प्रलीयन्ते तत्रैवाव्यक्तसंज्ञके।।8.18।।

avyaktād vyaktayaḥ sarvāḥ prabhavantyahar-āgame rātryāgame pralīyante tatraivāvyakta-sanjñake

avyaktāt—from the unmanifested; vyaktayaḥ—the manifested; sarvāḥ—all; prabhavanti—emanate; ahaḥ-āgame—at the advent of Brahma’s day; rātri-āgame—at the fall of Brahma’s night; pralīyante—they dissolve; tatra—into that; eva—certainly; avyakta-sanjñake—in that which is called the unmanifest

Translation

From the Unmanifested, all the manifested worlds proceed upon the arrival of the 'day'; upon the arrival of the 'night', they dissolve indeed into that which is known as the Unmanifested.

Commentary

8.18 अव्यक्तात् from the Unmanifested? व्यक्तयः the manifested? सर्वाः all? प्रभवन्ति proceed? अहरागमे at the coming of day? रात्र्यागमे at the coming of night? प्रलीयन्ते dissolve? तत्र there? एव verily? अव्यक्तसंज्ञके in that which is called the Unmanifested.Commentary When Brahma awakes? all manifestations? moving and unmoving (animate and inanimate) stream forth at the coming of the day from the

Avyakta or the Unmanifested. When Brahma goes to sleep? all the manifestations merge in the Unmanifested? for the cosmic night has set in.Coming of the day Commencement of creation.Coming of the night Commencement of dissolution. (Cf.IX.7and8)