yo maam pashyati sarvatra sarvam cha mayi pashyati |
tasyaaham na pranashyaami sa cha me naa pranashyati || 30 ||

One who sees me in all, and sees all in me, to him I am not lost, and he is not lost to me.
yaha : one who
maam : me
pashyati : sees
sarvatra : in all
sarvam : all
cha : and
mayi : in me
pashyati : sees
tasya : to him
aham : I
na : am not
pranashyaami : lost
saha : he
cha : and
me : me
naa : is not
pranashyati : lost
Shri Krishna now speaks to us directly as Ishvara. He says that the devotee who sees him in everything, and also sees everything in him, will have a permanent connection to him. In other words, Shri Krishna will never appear as distant or invisible to that devotee. It may seem a little confusing to hear this statement right after the previous shloka that said that one should see everything in the eternal essence. How does Ishvara fit into the picture?
Let us refer to our running example of the wave and the ocean. Imagine that a young child sees the ocean for the first time. Her intellect can only grasp visual, grosser objects. So her attention will immediately go towards the ocean, its colour, its size, the sounds it makes, the waves and so on. It will not be obvious to her that everything is water, because she has not reached that intellectual level yet.
Shri Krishna fully knows that most of us are children, even babies, on the spiritual journey. It will take a long time for our intellects to see the eternal essence everywhere. So until our perception stops operating on the level of names and forms, we have to find an easier way to see the eternal essence everywhere.
Therefore, Shri Krishna says that first, we should try to see everything in Ishvara and Ishvara in everything. Ishvara could be the form of Shri Krishna. It could be any other deity that we feel an affinity towards. It could also be our guru. No matter what form we choose, we should be able to view the form of Ishvara as the highest.
Now, most of us have the notion that Ishvara or God is a mysterious figure or force that is sitting far away in Kailash or Vaikuntha or somewhere us. But Shri Krishna, in the Gita, is telling us in this shloka that he is everywhere. It requires a radical shift in order to think this way. That is why in Indian culture, everything can become an object of worship, from a tree to a stone to a book, because Ishvara is present in everything. What is required is the understanding that comes through contemplation.
So therefore, if we truly begin to think that the whole world comprises Ishvara in our chosen form, there will never be a single moment where we are far from Ishvara.