Lord Krishna, a k a - God
Since we cannot see Vishnu, and only Arjuna and a few other disciplined sages had the experience of seeing Vishnu in His true form, we can only describe Vishnu by analogy.
Through this analogy we hope to open our mind to getting a glimpse of His true nature, and that it will guide our intellect to the path to permanent realization of His being. With this analogy we hope to catch a glimpse of Vishnu, that we might acquire the humility, love and discipline that is need on our journey towards unity with Him, that we may arise and aspire beyond our petty human concerns and egotism.
There is one thing I need to emphasize here. Western thought associates life, consciousness, intelligence and memory with biological creatures only. That such traits should be associated with galactic bodies, planets, pure energy does not really feature in the Western outlook.
In all the analogies I am going to make here, remember that these traits are a permanent, inherent feature in the phenomena I am describing.
Also remember that Lord Krishna is an avatar of this Being, without understanding the nature of this Being, one cannot understand the nature of the phenomenon that is (Lord) Krishna.