Text 7

ihaika-stham jagat krtsnam
pasyadya sa-caracaram
mama dehe gudakesha
yac canyad drastum icchasi

Translation

O Arjuna, whatever you wish to see, behold at once in this body of Mine! This universal form can show you whatever you now desire to see and whatever you may want to see in the future. Everything—moving and nonmoving—is here completely, in one place. 

Commentary by Srila Prabhupada 

No one can see the entire universe while sitting in one place. Even the most advanced scientist cannot see what is going on in other parts of the universe. But a devotee like Arjuna can see everything that exists in any part of the universe. Krishna gives him the power to see anything he wants to see, past, present and future. Thus by the mercy of Krishna, Arjuna is able to see everything.

Commentary by Sri Visvanatha Cakravarti Thakur

On this occasion (iha), this universe, which is impossible for you to see completely even if you wander within it for millions of years, is situated in just one part of my body (ekastham). See that universe and whatever else you desire to see, such as your victory or defeat (yac ca anyat) in my body, which is the shelter of the universe, being its cause.