Theosis (“deification,” “divinization”) is the process of a worshiper becoming free of hamartía (“missing the mark”), being united with God, beginning in this life and later consummated in bodily resurrection. For Orthodox Christians, Théōsis (see 2 Pet. 1:4) is salvation. Théōsis assumes that humans from the beginning are made to share in the Life or Nature of the all-Holy Trinity. Therefore, an infant or an adult worshiper is saved from the state of unholiness (hamartía — which is not to be confused with hamártēma “sin”) for participation in the Life (zōé, not simply bíos) of the Trinity — which is everlasting.
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.
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.
All of humanity is fully restored to the full potential of humanity because the Son of God took to Himself a human nature to be born of a woman, and takes to Himself also the sufferings due to sin (yet is not Himself a sinful man, and is God unchanged in His being). In Christ, the two natures of God and human are not two persons but one; thus, a union is effected in Christ, between all of humanity and God. So, the holy God and sinful humanity are reconciled in principle, in the one sinless man, Jesus Christ. (See Jesus’s prayer as recorded in John 17.)
According to Protopresbyter George Metallinos, Dean of the Athens University School of Theology, “For we Orthodox the unique and absolute goal of life in Christ is theosis, our union with God, so that man – through his participation in God’s uncreated energy – may become “by the Grace of God” that which God is by nature (without beginning and without end). This is what “salvation” means, in Christianity.”
As Christians we know that salvation is an ongoing process that, as believers, we are called to cooperate in. We are instructed to “Repent: for the kingdom of heaven is at hand” (Matthew 4:17). The Apostle Paul made clear the necessity of human cooperation when he told us to “work out your own salvation with fear and trembling; for it is God who is at work in you, enabling you both to will and to work for his good pleasure (Philippians 2:1–13)”.
Our salvation is a process by which we become more and more like Christ. Our faith is a free gift from God, not dependent upon anything we can do, but this life long process of salvation requires that we cooperate with God’s grace, that we might be transformed by the Holy Spirit, and made holy. If we are to spend eternity with God, transformation must take place.
The sole purpose of the Church is the salvation of every human person, whereby we are united to Christ, and transformed by Him in all holiness, and prepared for eternal life. Through the Church we hear the Good News, that Jesus is the Christ, the Messiah, and that he rose from the dead, and because of this we have eternal life. This work of salvation is a gradual, life-long process by which Christians become more and more like Christ. Our salvation begins the moment we commit ourselves to Christ, and within the abounding grace of the Holy Spirit, we are ever drawn closer in communion with God.
Theosis goes far beyond the simple restoration of people to their state before the Fall. Because Christ united the human and divine natures in his person, it is now possible for us to experience closer fellowship with God than Adam and Eve initially experienced in the Garden of Eden. 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.
With love in Christ,