Bhagavad Gita, Chapter 13, Verse 17

Impartible, yet It exists as if divided in beings: It is to be known as sustaining beings; and devouring, as well as generating them.

Appearing divided across countless beings doesn't actually mean being divided, that real distinction is drawn plainly here.

Krishna names himself as whole even while showing up differently in every living thing. Real unity is described as staying intact underneath apparent multiplicity.