Báli, thy foe, who stole away Thy wife this vengeful hand shall slay. These shafts which sunlike flash and burn, Winged with the feathers of the hern, Each swift of flight and sure and dread, With even knot and pointed head, Fierce as the crashing fire-bolt sent By him who rules the firmament, Shall reach thy wicked foe and like Infuriate serpents hiss and strike.

In plain words: Rama promises to kill Bali, Sugriva's brother, who stole Sugriva's wife. He describes his arrows as bright as the sun, as strong as Indra's thunderbolt (Indra is the king of the gods), and as deadly as angry snakes.