। ॥ ५५६ ॥
In plain words
An actor is still just himself whether he's wearing the costume or not. In exactly the same way, the greatest knower of Brahman is always simply Brahman - and never, for even a moment, anything else.
Close to the Sanskrit
Just as an actor [remains the same person] whether his costume is present or absent, so too the most excellent knower of Brahman is ever Brahman alone, nothing else.