In plain words
The poet, to his heart: Other than repeating what the Veda and those who follow it have already said, no one can know even one part of his greatness; and he is not one who can be known, except by those free of the flaw [of turning to other means]. Other than bowing to him who dwells in the minds of the stainless and living on so, is it possible for us even to speak of him? Tell me, foolish heart.