Then the man of unwholesome deeds boils in water infested with worms. He cannot stay still--the boiling pots, round and smooth like bowls, have no surfaces which he can get hold of. Then he is in the jungle of sword blades, limbs mangled and hacked, the tongue hauled by hooks, the body beaten and slashed. Then he is in Vetarani, a watery state difficult to get through, with its two streams that cut like razors. The poor beings fall into it, living out their unwholesome deeds of the past. Gnawed by hungry jackals, ravens and black dogs, and speckled vultures and crows, the sufferers groan. Such a state is experienced by the man of unwholesome deeds. It is a state of absolute suffering. So a sensible person in this world is as energetic and mindful as he can be.

(Buddha Sakyamuni)