। ॥ ४९३ ॥
In plain words
I am not 'this' and I am not 'that' either - I am the light by which both 'this' and 'that' are even seen at all. Supreme, pure, with no inside or outside left to speak of, complete. I am Brahman itself, without a second.
Close to the Sanskrit
I am not 'this,' nor am I even 'that' - I am the illuminator of both, the supreme, the pure; void of outer and inner, full - I am verily Brahman, without a second.