The Self in All Things — Aham Brahmasmi
The Teaching
In the beginning, this universe was Brahman alone, and it knew only itself, thinking: "I am Brahman." Therefore it became the All. Whoever among the gods became awakened to this also became that All; the same was true among sages, the same among humans.
Seeing this, the seer Vamadeva understood: "I was Manu and the sun." And even now whoever knows "I am Brahman" becomes this All.
Now if a person worships another deity thinking "he is one and I am another," that person does not know. Just as many animals serve a human, so too each person serves the gods when they remain in ignorance of their true nature.
Commentary
Aham Brahmasmi, I am Brahman, is the second of the four Mahavakyas. Where Chandogya's Tat Tvam Asi is addressed to the student (you are that), Brihadaranyaka's formulation is the first-person realization: I am Brahman.
The remarkable final lines, that it is not pleasing to the gods that humans should know this, echo the Gnostic insight that institutional powers have an interest in keeping human beings from recognizing their divine nature.
John's Gospel makes the same point: 'the world did not recognize him.' The Logos/Brahman/Tao is everywhere present and everywhere unrecognized by those who have been taught to look everywhere except within.