Krishna says, "I am the seed of all existence. There is nothing moving or unmoving that can exist without Me (10.39). There is no end to my divine manifestations. What I have told you is merely an indication of the extent of my opulence" (10.40).
HE is the seed of existence and in contemporary scientific understanding this seed is called the 'big bang'. Existence is like a massive tree that has grown from a small seed. The fruits of such a tree would find it difficult to comprehend this reality and tend to identify with one branch or another. Similarly, we too tend to identify with one manifestation or another. This leads to divisions and differences we perceive around us.
Krishna further says, "Know that in all cases whatever in existence is powerful, glorious and beautiful, ensues from but a spark of my splendor" (10.41). At the ignorance level, when one sees power or beauty in others, one might end up with jealousy or a desire to own it. This is nothing but misery. Alternatively, one may end up becoming a part of a cult or sect with blind faith.
The next level is to use them to motivate oneself to attain them. The final state is to remember HIM when we see the powerful, glorious and beautiful. This is nothing but the state of a witness or a 𝙔𝙤𝙜𝙞 .
Krishna concludes the tenth chapter of the Bhagavad Gita titled 𝙑𝙞𝙗𝙝𝙪𝙩𝙞 𝙔𝙤𝙜𝙖 and says, "But what need is there for all this extensive knowledge. I sustain the entire universe by a mere portion of myself" (10.42). A small portion of HIM is what we see as our universe. This leads to today's scientific understanding of the multiverse where we live in a universe that follows a set of physical rules and other universes follow another set of rules.