Supersoul: Localized Aspect of Supersoul

Q. I have a question related to the chariot analogy of the living entity. In the Katha Upanishad a description is given of a chariot drawn by 5 horses representing the senses, the mind the reins, the charioteer the intelligence and the passenger the soul.

My understanding is that as long as the soul/passenger is asleep, the living entity is conditioned, as he has no proper direction and undergoes repeated "birth and death" in the material world.

Q. According to BG 18.61 the Supreme Lord is situated in everyone's heart. But then according to Bramha Samhita, Paramatma is also situated within every atom. "andantarasatam paramanu chayantarastam." Now if I say He is situated in my heart, is He not in my hand as He is already present within every atom? What does it mean when it is said that He is present within every atom.