The statement by St. Athanasius of Alexandria, "The Son of God became man, that we might become god", [the second g is always lowercase since man can never become a God] indicates the concept beautifully.
II Peter 1:4 says that we have become " . . . partakers of divine nature." Athanasius amplifies the meaning of this verse when he says theosis is "becoming by grace what God is by nature" (De Incarnatione, I).
What would otherwise seem absurd, that fallen, sinful man may become holy as God is holy, has been made possible through Jesus Christ, who is God incarnate.
Naturally, the crucial Christian assertion, that God is One, sets an absolute limit on the meaning of theosis - it is not possible for any created being to become, ontologically, God or even another god.
Through theoria, the knowledge of God in Jesus Christ, human beings come to know and experience what it means to be fully human (the created image of God); through their communion with Jesus Christ God shares Himself with the human race, in order to conform them to all that God is in knowledge, righteousness and holiness.
Theosis also asserts the complete restoration of all people (and of the entire creation), in principle.
This is built upon the understanding of the atonement put forward by Irenaeus of Lyons, called "recapitulation."
For many fathers, theosis goes beyond simply restoring people to their state before the Fall of Adam and Eve, teaching that because Christ united the human and divine natures in his person, it is now possible for someone to experience closer fellowship with God than Adam and Eve initially experienced in the Garden of Eden, and that people can become more like God than Adam and Eve were at that time.
Some Orthodox theologians go so far as to say that Jesus would have become incarnate for this reason alone, even if Adam and Eve had never sinned.
Spend some time digesting this, then we'll revisit Theosis.
Simple, straight forward answer: who is Jesus?
Naturally, the crucial Christian assertion, that God is One, sets an absolute limit on the meaning of theosis - it is not possible for any created being to become, ontologically, God or even another god.
BTW 1010 you have your own Gorilla to deal with...
Answer my question...
Here junior, you need to chew on this as well. Athanasius himself clarified this very thing in his third treatise against the Arians: To become as the Father is impossible for us creatures. (http://www.archive.org/stream/selecttreatises00newmuoft/selecttreatises00newmuoft_djvu.txt)
Spend some time being able to DEFINE the words used based upon the author’s use - not your bubble gum pop.