The Doctrine of Theosis
A Series of Brief Reflections on Salvation as Deification
A Series of Brief Reflections on Salvation as Deification
Incarnation and Divinization
In the Eastern Catholic tradition, which is also reflected in certain paragraphs of the Catechism of the Catholic Church issued in 1992, the doctrine of salvation is called theosis, and it centers on the deification of man by grace [see Catechism of the Catholic Church, nos. 460, 1129, 1265, 1812, 1988, 1999]. This doctrine is fundamental to the teaching of the Church Fathers, who held that "God became man, so that man might become God" [St. Augustine, "Sermo 13 de Tempore," from The Office of Readings, page 125, (Boston: St. Paul Editions, 1983)]. Thus, the whole point of the incarnation of God is the deification of man.
As I indicated above, this teaching is reflected in the Catechism in several places, most especially in paragraph 1988 which reads as follows: "Through the power of the Holy Spirit we take part in Christ's Passion by dying to sin, and in His Resurrection by being born to new life; we are members of His Body which is the Church, branches grafted onto the Vine which is Himself: '[God] gave Himself to us through His Spirit. By the participation of the Spirit, we become communicants in the divine nature. . . . For this reason, those in whom the Spirit dwells are divinized'" [Catechism of the Catholic Church, no. 1988]. Deification by grace, i.e., becoming sons of God in the Only Begotten Son of God, is the whole point of the incarnation, life, passion, death, resurrection and ascension of our Lord.
Thus Mary, as the exemplar of the Church, having been assumed body and soul into Heaven, has experienced theosis and has been divinized by grace, and so she has been conformed perfectly to the likeness of her Divine Son, as one day all those who are saved shall be. This does not involve the destruction of her humanity, for she remains fully human, but she has been truly divinized by the grace of Almighty God.
This doctrine must not be thought of in a "Mormon" way, as if men become little gods with their own planets, but must be understood as a true deification of man and as an intimate communion of man with God in Christ. It must never be reduced to a mere metaphor, because by his incorporation into Christ, man is really made a partaker of the divine nature [see, 2nd Peter 1:4]. This does not involve a change in man's essence, but entails an indwelling of God's Spirit within the human person, enlivening both body and soul to everlasting life. There is an analogy between the incarnation and deification, which is most clearly indicated in the prayer of the priest during the offertory at Mass when he mixes the water with the wine and says, "By the mystery of this water and wine, may we come to share in the divinity of Christ, who humbled Himself to share in our humanity" [The Sacramentary, (New York: Catholic Book Publishing Co., 1985), page 370].
I will end with an extended quotation from the Pope's Apostolic Letter Novo Millennio Ineunte in which he speaks of this powerful mystery: "Jesus is the new man (see Eph 4:24; Col 3:10) who calls redeemed humanity to share in His divine life. The mystery of the Incarnation lays the foundations for an anthropology which, reaching beyond its own limitations and contradictions, moves towards God Himself, indeed towards the goal of divinization. This occurs through the grafting of the redeemed on to Christ and their admission into the intimacy of the Trinitarian life. The Fathers have laid great stress on this soteriological dimension of the mystery of the Incarnation: it is only because the Son of God truly became man that man, in him and through him, can truly become a son of God" [Pope John Paul II, Novo Millennio Ineunte, no. 23]. The process of deification does not involve the destruction of the distinction between God as the Creator and man as the created, for this distinction always remains, but by grace man is truly elevated into the very life and energy of the Trinity.
Copyright © 2004 - Steven Todd Kaster
Grace Restores Man's Likeness to God
As I indicated in my previous post, the doctrine of theosis is clearly taught by the prayer in the Roman Rite said by the priest when he pours a small amount of water into the chalice filled with wine at Mass, and says, "By the mystery of this water and wine may we come to share in the divinity of Christ, who humbled Himself to share in our humanity" [The Sacramentary, (New York: Catholic Book Publishing Co., 1985), page 370]. This ancient prayer is connected to the teaching of St. Cyprian of Carthage (ca. AD 253), who explained that the wine is a sign of the blood of Christ, while the water is a sign of the people of God. The mixture of these two elements in the one cup brings about the deification of humanity, because in mixing them together both the assimilation of man to Christ and the association of humanity with all that the Lord has accomplished through His redemptive incarnation is signified [see Ancient Christian Writers: The Letters of St. Cyprian, vol. 3, Epistle 63, no. 13:1-2, (New York: Newman Press, 1986), vol. 46 in the series, page 105]. Thus, the mixing of the water and wine during the liturgy symbolizes the indissoluble bond between Christ and His Body the Church, while also signifying the unbreakable bond in the Hypostatic Union between the Divine and human natures in the one person of Christ.
Let me once again emphasize that theosis does not involve a type of transubstantiation of man's nature into the divine nature, because that would not bring about man's deification, but instead would involve his annihilation. Theosis involves a true divinization (theopoiesis) of man, in which the divine likeness (theoeideis) lost by sin is restored, but this process is neither pantheistic nor monistic, and so man is not going to be absorbed into the divine nature; instead, he participates in the uncreated divine eneriges (grace) which flow out from the divine essence. Ultimately, theosis concerns God's gift to man of a share in His own divine life and energy, it involves an elevation of man to a state of existence that exceeds his own natural capabilities, and so what Christ is by nature, man becomes by grace. The Catechism of the Catholic Church, quoting several ancient and medieval sources, says the following about theosis, "The Word became flesh to make us 'partakers of the divine nature.' 'For this is why the Word became man, and the Son of God became the Son of man: so that man, by entering into communion with the Word and thus receiving divine sonship, might become a son of God.' 'For the Son of God became man so that we might become God.' 'The only-begotten Son of God, wanting to make us sharers in His divinity, assumed our nature, so that He, made man, might make men gods'" [Catechism of the Catholic Church, no. 460]. Finally, it should be noted that this doctrine is a part of the universal patrimony of the Church, and as such it has been taught by both the Greek and the Latin Fathers. This doctrine was only denied during the Reformation, because the Reformers distorted the meaning of justification and sanctification (i.e., deification), reducing them both to a mere legal fiction. The best way to combat the doctrinal errors of the Protestant Reformers is to assert fully and unequivocally the divinization of man by God's grace.
Copyright © 2004 - Steven Todd Kaster
✠ Icon of the Sunday of Orthodoxy ✠
The Uncreated Light of God in the Saints: A Defense of Veneration
In contemporary theological circles, a trend toward reductionism seeks to categorize the veneration of the saints as a dispensable "pious option." This approach is not merely a matter of differing tradition, but a failure to grasp the profound reality of the Incarnation. Taking this into account, it becomes clear that by praying to the saints, one honors Jesus who made the saints divine and holy in the first place. Because Christ is the source of all holiness, He is honored whenever the saints, who have been assimilated (homoiosis) to Him by participation in the divine energy, are venerated. In fact, the whole point of the Incarnation is to elevate humanity into the uncreated life and glory of the Holy Trinity; therefore, devotion to the saints can never become "unnecessary," for to venerate them involves honoring the holiness of God present within them.
Furthermore, when one fails to venerate those who have been made holy by God, one fails to honor the source of that holiness, i.e., God Himself. Indeed, insofar as the Christian faith is a holistic reality, it follows that one cannot hold that certain elements, no matter how unimportant they may appear to be to some individuals, are dispensable. This idea of "optional" veneration fails to recognize the power of God’s uncreated energy present within the saints, a recognition made manifest throughout the Church's liturgical life, especially in the sanctoral cycle, which commemorates their feasts throughout the year. Veneration of the saints, of icons, and of relics is never a mere tool or a means to an end; it is an end in itself, for this pious practice involves the recognition of God’s holiness that is made manifest through the Incarnation of Christ and His Paschal Mystery.
Moreover, the Christian faith should not be reduced to certain "key truths." This reductionism distorts the "hierarchy of truths," promoting the false view that some mysteries of the faith are dispensable. However, the hierarchy of truths concerns the interrelationship that exists between the mysteries of the faith, and not the false notion that some truths are "more" fundamental than others. In the Byzantine tradition, a saint and his icons and relics are infused with the uncreated divine energy of God; and because there is a hypostatic relation of name between the saint, as the prototype, and his earthly representations, it follows that these things (i.e., his icons and relics) are a true manifestation — a theophany — of his personal presence in the liturgical and paraliturgical life of the Church.
Finally, these practices are not mere "disciplines" required by the canonical tradition, nor are they foreign sensibilities imposed by force upon the Christian faithful by the ministerial hierarchy. In the life of the Christian East, the veneration of the Holy Theotokos and the saints, whether in their icons or relics, is an integral part of the Divine Liturgy itself. These devotions arise naturally as a gift of faith and reflect the constant dogmatic belief of the Church. To ignore the saints who have been deified by divine grace is an affront to God, for they — like the Church herself — are a perpetual extension of the Incarnation throughout space and time. Ultimately, a true and living devotion to the saints always leads to the adoration of the Holy Trinity, for He is the cause of holiness in the saints and in the whole Church.
Copyright © 2004, 2026 - Steven Todd Kaster (This text was reworked and revised on 21 January 2026)
Theosis Involves No Essential Change in either God or Man
The Fathers of the Church are insistent that deified man's participation in the divine nature does not mean that he participates in either the divine essence (ousia), which is and remains wholly incommunicable and incomprehensible, nor in the personal (hypostatic) reality of any one of the three divine persons, because personality is not something that can be communicated or imparted from one person to another. The divine essence and the personal subsistent (hypostatic) reality of the three divine persons are utterly transcendent and incommunicable properties of God. So man is not absorbed by an essential participation in the divine nature, nor are human persons added to the Trinity; instead, through the process of deification (theosis) man participates in the uncreated divine energies (energeiai) which flow out from the divine essence as a gift to humanity from the three divine persons. In other words, by a completely unmerited gift of grace, man is elevated to a participation in the divine nature through the uncreated divine energies (energeiai), and this involves no essential change, nor personal (hypostatic) addition, to either God or man; instead, it entails an abiding communion (koinonia) of life and love between the Holy Trinity and humanity.
Copyright © 2004 - Steven Todd Kaster
Theosis: The Vision of God
Theosis is the union of man with God in a vision of the Uncreated Light that is given by Him as a pure gift of His grace, and which the West calls the Beatific Vision. It is important to note, that this divine vision must not be reduced to a mere intellectual participation in God, nor must it be held to involve a noetic vision of the divine essence itself, for the divine essence is utterly beyond any form of participation. Rather, the vision of God properly understood, which the West refers to as beatific, involves the sanctification of the whole of the human person (body and soul) as he enters into God's presence through the uncreated divine energies; for such a man has been fully divinized by grace. But it must also be borne in mind, as St. Gregory of Nyssa taught, that although divinization is complete in one sense at the moment of death, the process of theosis is in reality an ongoing and eternal progression into God; and so, a man who is divinized by the Lord's uncreated energy will be more and more divinized throughout all eternity (epektasis).
Now in the case of a soul which has not yet received its resurrected body, there is a sense in which it is not experiencing the Vision of God in its disembodied state as fully as it will on the day of the resurrection, because the body also participates in the eikon Theô; and so redemption involves the salvation of the whole man, body and soul, and not merely the spiritual principle of his being. In other words, theosis is fully realized when the whole man, body and soul, enters into the vision of God, because once that happens, he will never leave the Lord's presence as he stretches eternally into God, moving from glory to glory. Yet, as indicated above, prior to the general resurrection, the soul in God's presence still awaits its definitive fulfillment in the general resurrection at the time of Christ's Parousia when it will receive its resurrected body.
This kind of mystery is similar to the mystery surrounding the particular and the general judgments. The fact that a person is immediately judged upon his death (i.e., the particular judgment); and yet, he awaits the definitive completion of that initial judgment in the general judgment at the end of time, does not mean that the particular judgment at the moment of death is somehow defective. Because it is important to remember that a person who is judged to be in a state of grace at his particular judgment, and who is ready to enter into the vision of God, will not have that judgment of God rescinded at the end of time. The general judgment at during the eschaton will confirm and make definitive the particular judgment already received. These two judgments form a single whole, i.e., a single complexus, and the same is true with theosis, because it is both complete at death, and yet it continues throughout eternity.
There are many mysteries like this. The Parousia of Christ itself (i.e., His glorious Second Coming) is involved in a similar mystery, for the Parousia happens at every Divine Liturgy under the veil of the sacred signs of bread and wine; because as we say during the Eucharistic liturgy, "Blessed is He who comes in the name of the Lord," and He really comes among us during the liturgy. Yet, the Parousia will only definitively happen at the end of time, when Christ visibly returns and judges the entire world. Be that as it may, both experiences of the Parousia, i.e., the one that occurs during the Divine Liturgy, and the one that occurs at the end of time, are real and mysteriously complete in their own way; and yet, only the one at the end of time is definitive.
Copyright © 2004, 2026 - Steven Todd Kaster (This text was revised on 17 January 2026)
Theosis and the Different Modes of Union in God
Any man who has been justified by the grace of our Lord Jesus Christ has been divinized through his participation in God's uncreated energies, and that means that deification is an ontological reality, and not merely a metaphorical or accidental reality. Now, it should be noted that there are three modes of union in God: the first mode of union involves a participation in the divine essence, and this is experienced only by the three divine hypostases (i.e., the Father, the Son, and the Holy Spirit); the second mode of union is called hypostatic, and only the incarnate Logos experiences this mode of union; and the third mode of union involves a participation in the divine energies, and this mode of union is experienced by all those who have been made partakers of the divine nature by Christ's incarnation and His Paschal Mystery [see 2 Peter 1:4]. Thus, divinization involves a real participation in God's own nature through His uncreated energies, and as a consequence of this, man truly becomes divine and uncreated at the level of energy, while remaining a created being in his own proper essence. In other words, salvation is the elevation of man into God, for as St. Athanasius said, "God was made man that we might be made God" [St. Athanasius, De Incarnatione Dei Verbi, 54:3].
Copyright © 2005 - Steven Todd Kaster
Theosis and Redemptive Suffering
The process of theosis involves redemptive suffering (cf. Romans 8:14-23), but suffering itself is not the end goal. Thus, within the Byzantine doctrinal, spiritual, and liturgical tradition, the point of all divine activity (energeia) is the resurrection to new life, i.e., the transfiguration of humanity in Christ, which ultimately transcends suffering just as the resurrection transcends the cross.
That said, the cross of course is necessary to salvation, just as the incarnation, resurrection, and ascension are necessary for salvation, but — as I indicated above — the cross is not itself the final objective; instead, the sacrificial death of Christ serves as a focal point through which the incarnate Logos passed in order to triumph over death, for as the Byzantine liturgy proclaims, "Christ is risen from the dead, by death He conquered death, and to those in the graves He granted life." In other words, the process of theosis, which iconically mirrors the self-emptying (kenosis) of Christ in the incarnation, never ends merely in redemptive suffering, but must transcend the limitations of human nature through a real participation in the life-giving energies of the Holy Spirit, Who draws man up into the uncreated life and glory of the tri-hypostatic God by making him a partaker of the divine nature (cf. 2nd Peter 1:4).
Copyright © 2007 - Steven Todd Kaster