''I see the forces that hold the universe together.''

Does it mean Xerath is aware of celestial beings even though he never met with them in physical way? What if he can feel Aurelion Sol because of his celestial form? Or he is just being arrogant fuck?

Maybe Aurelion Sol and Xerath have a connection between their souls. In the end Aurelion Sol says he feels every single star in his heart.

I think Aurelion Sol and Bard are two of those entities who hold the universe together. Bard overcomes the universal catastrophes, Aurelion Sol balances energy and matter.