Musar para sa Exodo 33:21

First of all, the very premise that someone would assume the world to be G–d’s arena , i.e. limiting Him, is totally strange. Why would we need a verse from Scripture to refute such thinking? Secondly, why is there a need for two separate verses proving that the world is not G–d's place but vice versa (a further verse in Exodus 33,21 where G–d says to Moses: "Here, there is a מקום beside Me," in addition to the verse in Psalms 90,1)?