If we have read the Brihadaranyaka Upanishad, we may have come across the mention of a rishi named Vamadeva, who is said, upon realising Brahman, to have “become Manu and Surya”. They feature in 1.4.10,
In the beginning, Brahman was this. It knew only itself: “I am Brahman.” Through that it became all. Whichever of the devas woke up to it became that; whichever of the rishis, likewise; whichever of human beings, likewise. Seeing that, the rishi Vamadeva realised: “I have become Manu and Surya too.”
Why was Vamadeva’s statement considered significant enough to include and explain in the Upanishad? How does saying he has “become Manu and Surya” signify realisation of Brahman?