On Theosis, or Divinization
What does it mean to be “partakers of the divine nature”?
“For by these He has granted to us His precious and magnificent promises, in order that by them you might become partakers of the divine nature, having escaped the corruption that is in the world by lust” (emphasis added) – 2 Peter 1:4, NASB.
As defined by the Orthodox Church, deification (theosis) postulates that a Christian can become subjected to
God’s full and perfect penetration . . . in which [state of being] the operations and energies of human nature cease, having been replaced by the Divine Operations and Energies. 
Though it has been part of “the spirituality” of the Orthodox Church for centuries, belief in divinization or theosis is emerging amongst today’s evangelicals.
Over two decades ago, Al Dager noted a trend among some Charismatics:
But we are now hearing from prominent teachers in the Christian media that man was created with a divine nature which was lost due to the introduction of sin. By being born again by the Spirit of God we lose our sin nature and regain our divine nature. 
Greg Boyd, who advocates both open theism and contemplative spirituality, forthrightly states:
We no longer have a “sinful nature”. 
To this point (though personally I do not believe he believes in deification), John MacArthur has written that early believers “were little Christs,” because they were first called Christiani at Antioch (i.e., “belonging to the party of,” Acts 11:26).  Though Jesus warned of “false Christs,” neither He nor His apostles called believers “little Christs” (Matthew 24:24; cf. 1 John 2:18).
Again, MacArthur’s inference that God “was right inside” the pagan philosophers at Mars Hill is troubling.  God is right inside believers only! The Apostle Paul wrote: “Now if any man have not the Spirit of Christ, he is none of his” (Romans 8:9; cf. John 3:3, 7).
Yet if scriptural precedent exists for the Christian to attain unto divinity,
The only biblical text which seems to bear directly on deification is II Peter 1:4, where the destiny of Christian believers is described as becoming “partakers of the divine nature”. 
Dager too noted that the man-becomes-god teaching “is based upon a theosophical interpretation of II Peter 1:4 . . .” 
So the question becomes, does Peter’s reference to partaking of the divine nature support the teaching that in this life a Christian can become deified? On the face of it, Peter might appear to be teaching that possibility. But upon a deeper investigation of the text, he does not.
To understand “partakers of the divine nature,” the context, grammar and syntax of Peter’s statement needs to be attended to, because if we understand what the apostle really communicated to the believers of that era, then we will be clear as to what he means for believers today. Unto this understanding, the following translation of 2 Peter 1, verse 4, is offered:
For by His own glory and excellence, the Lord Jesus has granted to us His precious and magnificent promises in order that by them—His precious and magnificent promises—we participate in/with the divine nature, having escaped the corruption that is in the world by lust. 
To understand what Peter stated in this verse, several points can be noted, some of which are obvious in the English text, and others that are not. In noting these points, it will become clear that the apostle was not teaching deification, that in this life Christian souls can be so consumed of divinity that the operations and energies of their human nature cease (i.e., a theotic state of being).
First, let it be stated that contrary to the prevalent Hellenistic philosophy of his day—that once-upon-a-time pre-existent human souls were part of deity, that amidst life’s material matrix these souls have lost consciousness of their divinity, and therefore that the goal of the soul in this life is to recover the lost consciousness of feeling oneness with God—Peter’s text assumes humans do not possess the potential to recover a lost divinity. As Köster states,
2 Pet. 1:4 presupposes the distinction between our weak mortal nature and the divine essence. 
Kelly adds that,
Union with God’s being was not the natural possession of man but the effect of God’s drawing him to Himself. 
So Peter’s statement contradicts the prevailing Gnostic and Platonic notion of his day; namely, that once-upon-a-time the human soul, whether individually or collectively, was part of God. This theosophical view of reality is current among Charismatics within the New Apostolic Reformation and Latter Rain movements as well as today’s New Age/New Spiritualists.). 
Peter’s statement indicates that there was never a time when pre-existent souls either possessed or participated in divinity. Therefore, in stating that Christians partake of the divine nature, Peter is not borrowing from Hellenistic philosophy as presupposed by many New Testament scholars. In fact, he is contradicting that idea!
Second, participation in the “divine nature” is in accord with the “precious and magnificent promises” of Jesus. In his book The Mystical Union of the Eastern Church, Vladimir Lossky states concerning the false teaching of deification in Christendom’s history:
If God has given us in the Church all the objective conditions, all the means that we need for the attainment of this end [i.e. attaining théosis], we, on our side, must produce the necessary subjective conditions: for it is in this synergy, in this co-operation of man with God, that the union is fulfilled. This subjective aspect of our union with God constitutes the way of union which is the Christian life. 
Clearly, the apostle Peter understood that any participation in the “divine nature” is not based upon synergy (God and man working together), but by God’s grace according to His precious and magnificent promises. If synergy between God and man is involved, it will only be in the sanctification process whereby the Holy Spirit enables individual Christians to incorporate virtues of godliness into their lifestyles (2 Peter 1:5-7; See the seventh point below.).
Third, within the clause “you might become partakers,” both the verb and noun are plural.  The fact that the apostle addresses all his readers indicates that participation in the “divine nature” is not restricted to adepts, to persons specializing in spirituality. It is not for elite Christians who through spiritual disciplines or ascetic practices might attain deification (cf. Colossians 2:20-23), but for all believers who for reason of divine promises and the Spirit’s indwelling presence, God enables to live sanctified lives on earth as they await the consummation of sanctification, their glorification in heaven (Romans 8:29-30). As John confirms: “Beloved, now are we the sons of God, and it doth not yet appear what we shall be: but we know that, when he shall appear, we shall be like him; for we shall see him as he is” (1 John 3:2; cf. 2 Corinthians 3:18).
Participation in the divine nature is not discriminatory. It’s on the group plan!
Fourth, we should note that as communicated by English translations, the verb “might become” connotes possible participation in the divine nature. This however, is not the sense of Peter’s statement.  Believers’ participation in the divine nature is actual not potential, and will exist in continuum until the time at which they arrive in the Lord’s presence. In accord with God’s plan and purpose, the time is coming when for reason of His “precious and magnificent promises,” participation in the divine nature will be brought to its appointed consummation (1 Peter 1:3-5). As Paul affirmed:
Being confident of this very thing, that he which hath begun a good work in you will perform it until the day of Jesus Christ. – Philippians 1:6.
For Christian believers, full participation in the divine nature, which is immortal and incorruptible, is future and awaits either our death or Christ’s Second Coming.
Fifth, we should note that the noun “partakers” (koinonoí) connotes “the basic idea of one who shares in what is common or shared by all and may be best translated ‘partner, participant’.”  Thus, partaking of the divine nature carries more the idea of doing than being. As Paul vouched for Titus: “he is my partner [koinonos] and fellow worker [sunergós] among you . . .” (2 Corinthians 8:23).
Further, it can be noted that the English preposition “Whereby” (KJV) that introduces 1 Peter 1:4 (Greek words, di’ hon) was used in ancient decrees pointing to the “personal expenditures of a benefactor . . . Here Peter declares that God’s boon [help, benefit] finds its source in his own ‘glory and virtue’.”  It is all from and of God.
Just because God gives a believer a spiritual share in His Corporation does not mean that, for reason of divinization, he or she owns it!
Sixth, and perhaps most importantly, we should note what the phrase “partakers of the divine nature” does not say (2 Peter 1:4). The Greek New Testament contains the following word order: theías [genitive adjective “divine”], koinonoí [nominative noun “partakers”], and phúseos [genitive noun “nature”].
Based upon Peter’s word choice, we can surmise that if he had intended to teach deification or theosis (thereby accommodating his statement to the Platonic-Gnostic philosophy of that era), he might have omitted the noun “partakers” (koinonoí). Then the phrase would have read that Christians were granted “precious and magnificent promises” so that they might become the divine nature (Greek theías phúseos).  But he did not.
Instead, he inserted a nominative noun “partakers” between an adjective “divine” and a noun “nature.” In doing so, Peter stated that while by regeneration Christians participate in the divine nature (1 Peter 1:3, 23), they are not and will not be consumed of it. As Lewis Smedes (1921-2002) wrote of the interaction of the divine and human natures within a regenerate soul:
Christ communicates Himself in a way that changes us without diminishing us, transforms us without deifying us, [and] Christianizes us without making us Christs. 
Seventh, in this context (2 Peter 1:4-7), partaking of the divine nature regards not so much a believer’s being as his/her doing. Faith does not live in a moral vacuum (Compare James 2:20, 26.). So having “escaped the corruption that is in the world by lust,” Christians are to apply and supply; to diligently seek to add “moral excellence” to faith. 
The moral excellence consists of a list of virtues in which the first virtue becomes foundational for the next, in which the latter grows out of the former—“knowledge . . . self-control . . . perseverance . . . godliness . . . brotherly kindness . . . [and] love” (2 Peter 1:5-7). In other words, by God’s grace, as believers build these virtues into their lifestyles, they participate in/with the divine nature. These virtues are God’s. Yet if believers fail to cultivate these virtues into their lives by His power, they do not participate in the divine nature. As these qualities grow in their lives, believers will “not carry out the desire of the flesh” (Galatians 5:19). In this context, to be a partaker in the divine nature has more to do with divine ethics than divine essence.
As in His incarnation Jesus partook of genuine humanity without becoming a sinner, so Christians partner in the divine nature without becoming God. While we fellowship in and with the divine nature, we don’t own it. Participation in the divine nature for Christian believers is relative, not absolute.
Vladimir Lossky summarizes the false teaching of deification in Christendom’s history:
God became man in order that man might become god, to use the words of Ireneus and Athanasius, echoed by the Fathers and theologians of every age. 
As Athanasius (c. 293-373) of Alexandria stated of Jesus:
For He was made man that we might be made God . . . 
He [Jesus Christ] was God, and then became man, and that to deify us . . . 
The implications of deification are far reaching. Its thinking extends to the false Roman Catholic teaching of justification where Christ’s righteousness is infused into subject Christians (partial divinization) thereby enabling them to do the works necessary to help God effect their justification. Belief in mystic divinization also affects the doctrine of the Eucharist where, by and around the Eucharistic elements, a real corporeal presence of Christ is invoked (i.e., consubstantiation), or where alchemically, the elements morph to become the body and blood of Jesus (i.e., transubstantiation) which, when ingested, impart the divine nature to communicants.
As regards our union with Christ, John Flavel (1627-1691), a nonconformist English-Presbyterian clergyman, states it is,
[Not] an essential union, or union with the divine nature, so that our beings are thereby swallowed up and lost in the divine Being. Some there be indeed that talk at that wild rate, of being godded into God, and christed into Christ; but O, there is an infinite distance between us and Christ, in respect to nature and excellency, notwithstanding this union. 
Yet we believers ought to rejoice in our union with Christ, a togetherness that, for reason of our being baptized in/with and by the Holy Spirit, is spiritual (1 Corinthians 12:13; See John 17:22-21.). But while Christ’s dwelling in believers is spiritual, it is not substantial. It is a union and communion facilitated by the Holy Spirit who sovereignly incorporates God’s presence, not essence, in believers, this grandest of all unions being activated by faith in the atonement for sins by the Lord Jesus Christ. Paul wrote that this hidden mystery, this musterion, then becomes, “Christ in you, the hope of glory” (Colossians 1:27). 
Daniel Whittle (1840-1901) wrote of this union in his hymn Christ Liveth in Me:
As lives the flower within the seed, As in the cone the tree,
So, praise the God of truth and grace, His Spirit liveth in me.
Christ liveth in me, Christ liveth in me;
Oh, what a salvation this, That Christ liveth in me! 
“For now we see through a glass, darkly; but then face to face: now I know in part; but then shall I know even as also I am known.” – 1 Corinthians 13:12, KJV.
 Protopresbyter Michael Pomazansky, Orthodox Dogmatic Theology: A Concise Exposition, Hieromonk Seraphim Rose, Translator and Editor (Platina, CA: St. Herman of Alaska Brotherhood, 2005): Footnote 27, 221.
 Albert James Dager, Vengeance is Ours: The Church In Dominion (Redmond, WA: Sword Publishers, 1990): 22.
 Gregory A. Boyd, Present Perfect: Finding God in the Now (Grand Rapids, MI: Zondervan, 2010): 164, Footnote 2.
 John Mac Arthur, Hard to Believe: The High Cost and Infinite Value of Following Jesus (Nashville, TN: Thomas Nelson, 2003): 125.
 Ibid. 207. MacArthur bases this deduction on Acts 17:28 where the apostle told the philosophers, “For in [the Lord] we live, and move, and have our being; as certain also of your own poets have said, For we are also his offspring.”
 Rowan Williams, “Deification,” The Westminster Dictionary of Christian Spirituality, Gordon S. Wakefield, Editor (Philadelphia, PA: The Westminster Press, 1983): 106.
 Dager, Vengeance, 22.
 The antecedents in Peter’s statement are obvious. Jesus’ own glory and excellence are sufficient cause for Him to grant believers precious and magnificent promises by which they become partakers of the divine nature.
 H. Köster, “phýsis [nature],” Theological Dictionary of the New Testament: Abridged in One Volume, Editors Gerhard Kittle and Gerhard Friedrich, Translated by Geoffrey W. Bromiley (Grand Rapids, MI: William B. Eerdmans Publishing Company, 1985): 1286.
 J.N.D. Kelley, The Epistles of Peter and of Jude (Peabody, Massachusetts: Hendrickson Publishers, Inc., 1969): 303.
 Dager, Vengeance, 22.
 Vladimir Lossky, The Mystical Union of the Eastern Church (Cambridge & London: James Clarke & Co. LTD, 1957):196.
 “Apart from its general use as a companion and fellow worker . . . koinonos is used in the plural of the recipients of the grace of in 2 Peter 1:4, where Christians are said to be partakers of the divine nature.” See Peter Toon, “Fellowship,” Evangelical Dictionary of Biblical Theology, Walter A. Elwell, Editor (Grand Rapids, MI: Baker Books, 1996): 256. Kelley’s observation that the consummation of the “promised grace” is “to the individual, rather than to Christians as a body” doesn’t do justice to the plural verb and noun. See Kelley, Epistles of Peter, 304.
 The phrase in order that we might become consists of a conjunction (Greek hína) and a verb (Greek génesthe) occurring in the aorist tense and subjunctive mood. The aorist tense may be understood as consummative, that participation in/with the divine nature had begun and would one day be consummated. When combined with the subjunctive mood, the conjunction “in order that” (Greek hína) indicates that “what God purposes is what happens and, consequently, hína is used to express both the divine purpose and the result.” See Daniel B. Wallace, Greek Grammar Beyond the Basics: An Exegetical Syntax of the New Testament (Grand Rapids, MI: Zondervan Publishing House, 1996): 473. Wallace also observes: “In many cases purpose and result cannot be clearly differentiated . . . As in Jewish and pagan thought, purpose and result are identical in declarations of the divine will.” (Ibid. 206)
 See William D. Mounce, General Editor, “Participant,” Mounce’s Complete Expository Dictionary of Old & New Testament Words (Grand Rapids, MI: Zondervan, 2006): 498.
 Gene L. Green, Baker Exegetical Commentary of the New Testament: Jude & 2 Peter (Grand Rapids, MI: Baker Academic, 2008): 184.
 “The genitive substantive functions semantically as the direct object of the verbal idea implicit in the head noun. This is common in the NT.” See Wallace, Greek Grammar Beyond the Basics, 116.
 Lewis B. Smedes, All Things Made New: A Theology of Man’s Union with Christ (Grand Rapids, MI: William B. Eerdmans Publishing Company, 1970): 188.
 It is recognized that full escape from the world’s corruption will occur either when believers die or Jesus Christ returns (His Parousia).
 Lossky, Mystical Theology, 134.
 A Select Library of the Nicene and Post-Nicene Fathers of the Christian Church, Second Series, Volume 4, Phillip Schaaf, Editor, “St Athanasius: Select Works and Letters, On the Incarnation of the Word,” 54.3 (Albany, Oregon: The Ages Digital Library Collection, 1997): 341.
 A Select Library of the Nicene and Post-Nicene Fathers of the Christian Church, Second Series, Volume 4, Phillip Schaaf, Editor, “St Athanasius: Select Works and Letters, Four Discourses Against the Arians” Discourse 1.11.39 (Albany, Oregon: The Ages Digital Library Collection, 1997): 852.
 Robert L. Dabney, “Union to Christ,” Lectures in Systematic Theology (Grand Rapids, MI: Zondervan Publishing House, 1972 Reprint of 1878 Edition): 616-617.
 John Flavel, The Method of Grace: How the Holy Spirit Works (Albany, OR: Ages Software, 1997): 35. Dabney adds: “We see nothing in the Bible to warrant the belief of a literal conjunction of the substance of the Godhead in Christ, with the substance of a believer’s soul.” See Dabney, Lectures, 616.
 The believer’s union with Christ is hidden; it has not yet been revealed (Colossians 3:3-4). In the sense that this union is hidden, it is mystical (mustika). “This is a great mystery [that of the husband-wife union]: but I speak concerning Christ and the church” (Ephesians 5:32, KJV). Many Puritan writers employ the word mystic to equate to the word mystery. However, their use of the word mystic does not “mean thereby, that . . . they adopted the views held by the ancient and medieval Mystics, who taught an essential oneness of the human intelligence with the substance of the Logos to be developed by quietism and asceticism.” See Dabney, Lectures, 616.
This may be how the fifth stanza of The Church’s One Foundation ought to be understood (“Yet she on earth hath union With God the Three in One / And mystic sweet communion With those whose rest is won.”). While there’s a contemplative mysticism that the Bible knows nothing of, there exists through the Holy Spirit a spiritual union and communion that believers have with Christ and each other. Because it’s hidden (a mystery), some believers call it mystical. I state this so that we will careful to distinguish an orthodox use of the word mystical from the heretical.
Personally, I believe the evangelical church’s failure to preach the union of a believer with Christ and with each other has created a vacuum into which theosophy and psychology now take up space, space that was formerly occupied by pastoral preaching on the spiritual life. If this be the case, shame on us.
 Daniel W. Whittle, “Christ Liveth in Me,” Hymns of the Christian Faith (Camp Hill, PA: Christian Publishers, 1978): 500.