This verse restates the identity “I am Brahman,” but now as a settled fact rather than a defensive reply to doubt. Chapter 15 describes the subsiding of all mental activity, and this declaration is the anchor: when the mind becomes quiet, what remains is precisely Brahman — formless and sat-cid-ānanda. The realization is not an affirmation one repeats, but the natural residue when no affirmation or negation is being made.