Krishna now turns to a subtle but important warning. Some people, he tells Arjuna, use beautiful, elaborate language to talk about the Vedas — flowery words that sound impressive and authoritative. They insist that the ritual portions of the Vedas are all there is, that nothing exists beyond them. They are, Krishna says plainly, lacking in discernment.
The key phrase is 'pushpitam vacham' — flowery speech. Flowers are attractive on the surface but have no nourishment in them. These speakers dress up their claims in ornate language, but their understanding stops at the surface. They know the letter of the text but miss the spirit behind it.
Krishna is not criticizing the Vedas. He is criticizing a particular mindset — the mindset that mistakes the map for the territory, that clings to rituals and promises of reward while missing the deeper teaching of self-knowledge and selfless action that the Vedas ultimately point toward.