Sanskrit
यथा प्रदीप्तं ज्वलनं पतङ्गाः विशन्ति नाशाय समृद्धवेगाः । तथैव नाशाय विशन्ति लोकाः तवापि वक्त्राणि समृद्धवेगाः ॥
yathā pradīptaṃ jvalanaṃ pataṅgāḥ viśanti nāśāya samṛddhavegāḥ tathaiva nāśāya viśanti lokāḥ tavāpi vaktrāṇi samṛddhavegāḥ
Translation
As moths with quickened speed will headlong fly Into a flaming light, to fall destroyed, So also these, in haste precipitate, Enter within Thy mouths destroyed to fall.
Annie Besant · The Bhagavad-Gita, translated by Annie Besant (4th ed., 1922) — Wikisource · Public Domain
Explanation
Where verse 28’s river had no will at all, the moth has one and uses it wrongly — flying toward the flame with “samṛddhavegāḥ,” gathered speed, as if hurrying toward safety rather than annihilation. Paired back to back, the two similes quietly stage the poem’s whole argument about self-destructive action: sometimes ruin looks like law (the river), and sometimes it looks like a choice that only seems eager (the moth). This is the moment verse 21 was pointing toward when it warned that warriors were about to enter these mouths “not to praise, but to be devoured” — the devouring has now fully arrived, description giving way to naked spectacle.