Svetaketu has come home after twelve years studying all the learning a young Brahmin was expected to acquire. He is proud of his attainments, proud to the point of arrogance. The question having been asked, Svetaketu asks his father how such instruction is imparted. In response his father instructs him. Gold itself is the reality.
All transformation is at root a matter of language, it is only nominal.
Iron itself is the reality. And his father agrees. His father now instructs Svetaketu by means of a sequence of vivid images. He invites Svetaketu to intuit his own oneness with the nothing from which all things flow. But this body of teaching represents the first step on the spiritual path.