VUTPATTIM CHA VINASHAM CHA, BHOOTHANAM AAGATHIM GATHIM,
VETTHI VIDYAM AVIDYAM CHA, SA VACHYO BHAGAVANITHI.
he who knows:
1. the birth and deathof pancha bhoothas,
2. the place from where pancha bhoothas come and go to at the end,
3. vidhya and avidhya
is called "bhagwan".
so, if "bhagwan" is just the person who has the knowledge of things, what is "everything"?
Again to square one..
I'l put your question in a different term:
The one who is
3.omniscient is God...
This is not Just a person's capacity...
Again every soul is the none other than the Omnipresent Brahmam and is everything.
But the biggest question is do we know that?
If you mean Bhagwan as a separate person -May be Saguna Brhman.. He is always in unification with Nirguna Brahmam and projects himself as an entity with form and action just fo our sake.
Now.. approach the question from another view point... The person who has the knowledge of things is Bhawagan...
By knowing the self, a person attain a state of oneness with the divine-brahmam and becomes Bhawagwan.