Having fallen into repeated births among the demoniac species of life, the demoniac sink down to the lowest state of existence.

What’s the lesson for all of us? Threefold (tri-vidhaṁ) is this gateway (idaṁ dvāraṁ) to hell (narakasya), which destroys (nāśanam) [the proper conception of] the self (ātmanaḥ) – lust, anger and greed (kāmaḥ krodhas tathā lobhas). Therefore (tasmād), one must give up (tyajet) these three (etat trayaṁ). (BG 16.21) When one is free (vimuktaḥ) from these (etair) three gateways to darkness (tamo-dvārais tribhir), one (naraḥ) acts (ācaraty) for the benefit (śreyas) of the soul (ātmanaḥ) and thereafter (tato) attains (yāti) the supreme destination (parāṁ gatim). (BG 16.22)

The demoniac quality fundamentally emerges from one’s willful neglect of scriptural injunctions. Giving up the rules and regulations of the scriptures (śāstra-vidhim utsṛjya), one who (yaḥ) acts (vartate) according to one’s whimsical desires (kāma-kārataḥ), such a person (sa) attains (avāpnoti) neither (na) perfection (siddhim ), nor happiness (na sukhaṁ), nor the supreme destination (na parāṁ gatim). (BG 16.23)

Krishna concludes the chapter with an important principle and a benevolent instruction. Scripture (chāstraṁ) is, therefore (tasmāc), our (te) basis (pramāṇaṁ) for determining (vyavasthitau) what is to be done and what is not to be done (kāryākārya). We should (arhasi) perform our duty (karma kartum) in this world (iha) fully aware of (jñātvā) the rules and regulations stated in the scripture (śāstra-vidhānoktaṁ). (BG 16.24)