Either an ordered universe, or a stew of mixed ingredients, yet still coherent order. Otherwise how could a sort of private order subsist within you, if there is disorder in the Whole? Especially given that all things, distinct as they are, nevertheless permeate and respond to each other.
This passage is one of many that Marcus wrote on the question of: is there a God, or are there just random atoms that govern the universe?
The Stoics would see beyond the question and arrive at the conclusion that whether a person believed in a God or Gods that govern the universe or if a person believed it was all chaos and random atoms, the response from a person ought to be the same. And that response is: live according to reason - be who you were meant to be; accept your fate regardless if you view it as coming from God(s) or from random events.
(see also Citadel p. 148)