The Essence of All
Brahman as the subtle essence pervading everything.
Like salt dissolved in water is present throughout yet invisible, Brahman pervades all existence as its subtle essence. Though unseen, it is the reality of all.
As salt dissolved in water cannot be seen yet is tasted everywhere, so is Brahman in all existence.
This metaphor illustrates Brahman's pervasive presence.
Chandogya Upanishad