Deification or theosis, according to Eastern Orthodoxy, is a process by which one becomes “one with God,” and this is seen as the goal of the Christian life. This unity with God is a mystical concept that is often misunderstood by Western thinkers. The Eastern Orthodox Church is staunchly Trinitarian, and the term deification should not be misunderstood to imply that a human being can actually become God or a god, nor does this amount to pantheism. It is said that man cannot become one with God in His essence, but he can become one with His energies. Love, for instance, is a divine energy, and it is possible for the believer to be fully united and overcome by God’s love.
Eastern Orthodox theologians point to a number of biblical passages to describe deification. Several are listed below:
Romans 12:2 speaks of being transformed by the renewal of our minds.
1 Corinthians 6:17: “But whoever is united with the Lord is one with him in spirit.”
Colossians 3:3: “For you died, and your life is now hidden with Christ in God.”
In Ephesians 3:19 Paul prays for the Ephesians that you will “know [God’s] love that surpasses knowledge—that you may be filled to the measure of all the fullness of God.”
2 Peter 1:4: “He has given us his very great and precious promises, so that through them you may participate in the divine nature, having escaped the corruption in the world caused by evil desires.”
The thinking behind the doctrine of deification runs along this line: one day we will be transformed into the image of Christ, and it should be our goal to become as much like Him as possible in this life. We do this by putting sin to death in our lives and practicing spiritual disciplines. Through these means, we can actually become united with God, and it is possible in this life. The Orthodox teaching of deification in many ways resembles the doctrine of entire sanctification taught by some Wesleyan groups.
What the Eastern Orthodox Church calls “deification” might be understood by evangelicals as the new birth and subsequent sanctification. But the Orthodox concept of deification takes sanctification further to include a mystical union with God. The biggest problem with the doctrine is not the term deification but the means to it, as taught by the Eastern Orthodox Church. According to the New Testament, we are united with Christ, filled with the fullness of God, filled with the Holy Spirit, and declared to be right with God on the basis of faith in Christ. It is not something that happens as the result of a (perhaps) lifelong pursuit of unity with God through effort and discipline. In Christ we have become “partakers of the divine nature” (2 Peter 1:14). The actual experience of this can ebb and flow, but the fact of it never changes.
The great question that must be answered by every religion that takes a holy God seriously is “how can a sinful man stand before God and be fully justified?” There are really only two answers. Either God accepts the sinner based on some effort on the part of the sinner to attain a state of righteousness or God accepts the sinner on the basis of Christ’s righteousness credited to the sinner. Unfortunately, the Eastern Orthodox process of deification seems to fall squarely within the first option.