From the unmanifest. The unmanifest is the state of sleep of Prajāpati; from that unmanifest the manifestations, that is, all creatures, marked as moving and unmoving, come forth, become manifest, at the coming of the day, the time of Brahmā's waking. Likewise at the coming of the night, the time of Brahmā's sleep, all the manifestations dissolve into that very thing already named, called the unmanifest. To set aside the faults of unearned gain and lost earning, to show that the scripture concerning bondage and liberation is fruitful in its working, and because, by force of the store of action rooted in the afflictions such as ignorance, the helpless host of beings comes to be again and again and then dissolves, and so to show that one should grow dispassionate toward transmigration, He says this.

There, at the time of the coming of Brahma's day, the manifest forms, which abide within the three worlds as bodies, senses, and the things and places of enjoyment, arise from the unmanifest, namely the body of the four-faced one. And in that very particular unmanifest state, the body of the four-faced one, at the time of the coming of night, they are dissolved.

This is a brief sub-gloss. For a fuller reading of this verse, see Madhusūdana, Śaṅkara, or Rāmānuja above.

Madhva's commentary treats verses 8.17 through 8.19 as a single passage; it is given in full at verse 8.17.