यथा नदीनां बहवोऽम्बुवेगाः समुद्रमेवाभिमुखा द्रवन्ति ।तथा तवामी नरलोकवीरा विशन्ति वक्त्राण्यभिविज्वलन्ति॥
yathā nadīnāṃ bahavo ’mbu-vegāḥsamudram evābhimukhā dravantitathā tavāmī nara-loka-vīrāviśanti vaktrāṇy abhivijvalanti
Word by word
The verse says
As the many rushing waters of rivers run toward the sea, so these heroes of the human world enter your blazing mouths.
In plain words
The image changes, and it is gentler than what came before.
Rivers running to the sea. Something every river does, that nothing about a river could prevent.
It is still the same event. What has changed is that it now looks like a direction rather than an attack.
Where you've felt this · in community
At the end of a match, forty thousand people get up and move toward the exits at the same time. Nobody is pushing. Nobody decided when to stand. If you stop walking you discover quite quickly that stopping is not one of the available options.
Going deeper
Two images for the same event, back to back, and the second one changes what the first one meant.
Verse 27 had mouths and teeth and crushing — an attack, with an agent. This has rivers reaching the sea, which has no agent at all and no malice in it. Nothing about the event has changed between the verses. Only the frame has.
That is preparing the ground for verse 32, where the answer, when it comes, will be a name rather than a motive.
And it is the same image Chapter 2 used for something entirely peaceful: desires entering a steady person as rivers enter the full and unmoving sea. The picture of rivers reaching the ocean can be consolation or annihilation depending on where you are standing, and the Gita uses it both ways without pretending they are different pictures.