In Eastern Orthodox Christian theology, the Tabor Light (also Light of Tabor, Tabor's Light, Taboric Light; Greek: Φῶς του Θαβώρ, also as Ἄκτιστον Φῶς, Uncreated Light, Θεῖον Φῶς, Divine Light; Russian: Фаворский свет) is the light revealed on Mount Tabor at the Transfiguration of Jesus, identified with the light seen by Paul at his conversion.
As a theological doctrine, the uncreated nature of the Light of Tabor was formulated in the 14th century by Gregory Palamas, an Athonite monk, defending the mystical practices of Hesychasm against accusations of heresy by Barlaam of Calabria. When considered as a theological doctrine, this view is known as Palamism after Palamas.
The view was very controversial when it was first proposed, sparking the Hesychast controversy, and the Palamist faction prevailed only after the military victory of John VI Kantakouzenos in the Byzantine civil war of 1341–1347. Since 1347, it has been the official doctrine in Eastern Orthodoxy, while it remains without explicit affirmation or denial by the Roman Catholic Church. Roman Catholic theologians have rejected it in the past, but Andreas Andreopoulos has said that now "the Western world has started to rediscover what amounts to a lost tradition. Hesychasm, which was never anything close to a scholar's pursuit, is now studied by Western theologians who are astounded by the profound thought and spirituality of late Byzantium." Speaking of the hesychast controversy, Pope John Paul II said the term "hesychasm" refers to a practice of prayer marked by deep tranquillity of the spirit intent on contemplating God unceasingly by invoking the name of Jesus. While from a Catholic viewpoint there have been tensions concerning some developments of the practice, the Pope said, there is no denying the goodness of the intention that inspired its defence, which was to stress that man is offered the concrete possibility of uniting himself in his inner heart with God in that profound union of grace known as Theosis, divinization.
In Eastern Orthodoxy
According to the Hesychast mystic tradition of Eastern Orthodox spirituality, a completely purified saint who has attained divine union experiences the vision of divine radiance that is the same 'light' that was manifested to Jesus' disciples on Mount Tabor at the Transfiguration. This experience is referred to as theoria. Barlaam (and Western Christianity's interpretation of apophaticism being the absence of God rather than the unknowability of God) held this view of the hesychasts to be polytheistic inasmuch as it seemed to postulate two eternal substances, a visible (the divine energies) and an invisible (the divine ousia or essence). Seco and Maspero assert that the Palamite doctrine of the uncreated light is rooted in Palamas' reading of Gregory of Nyssa.
Instances of the Uncreated Light are read into the Old Testament by Orthodox Christians, e.g. the Burning Bush a purported descendant of which is kept at the Saint Catherine's Monastery at Mount Sinai in the Sinai Peninsula.
Gregory Palamas defended Hesychasm in the 1340s at three different synods in Constantinople, and he also wrote a number of works in its defense. In these works, Gregory Palamas uses a distinction, already found in the 4th century in the works of the Cappadocian Fathers, between the energies or operations (Gr. energeies) of God and the essence (ousia) of God. Gregory taught that the energies or operations of God were uncreated. He taught that the essence of God can never be known by his creatures even in the next life, but that his uncreated energies or operations can be known both in this life and in the next, and can convey to the Hesychast in this life and to the righteous in the next life as a true spiritual knowledge of God (theoria). In Palamite theology, it is the uncreated energies of God that illumine the Hesychast who has been vouchsafed an experience of the Uncreated Light.
In 1341 the dispute came before a synod held at Constantinople and presided over by the Emperor Andronicus III Palaeologus; the synod, taking into account the regard in which the writings of the pseudo-Dionysius were held, condemned Barlaam, who recanted and returned to Calabria, afterwards becoming bishop in the Roman Catholic Church.
One of Barlaam's friends, Gregory Akindynos, who originally was also a friend of Gregory's, took up the controversy, and three other synods on the subject were held, at the second of which the followers of Barlaam gained a brief victory. However, in 1351 at a synod under the presidency of the Emperor John VI Cantacuzenus, Hesychast doctrine was established as the doctrine of the Eastern Orthodox Church.
Identification with the fires of hell
Many Orthodox theologians have identified the Tabor light with the fire of hell. According to these theologians, hell is the condition of those who remain unreconciled to the uncreated light and love of and for God and are burned by it. According to Iōannēs Polemēs, Theophanes of Nicea believed that, for sinners, "the divine light will be perceived as the punishing fire of hell".
According to Iōannēs Polemēs, Palamas himself did not identify hell-fire with the Tabor light: "Unlike Theophanes, Palamas did not believe that sinners could have an experience of the divine light [...] Nowhere in his works does Palamas seem to adopt Theophanes' view that the light of Tabor is identical with the fire of hell."
Palamism, Gregory Palamas' theology of divine "operations", was never accepted by the Scholastic theologians of the Latin Catholic Church, who maintained a strong view of the simplicity of God, conceived as Actus purus. This doctrinal division reinforced the east-west split of the Great Schism throughout the 15th to 19th centuries, with only Pope John Paul II opening a possibility for reconciliation by expressing his personal respect for the doctrine.
Roman Catholicism traditionally sees the glory manifested at Tabor as symbolic of the eschatological glory of heaven; in a 15th-century Latin hymn Coelestis formam gloriae (Sarum Breviary, Venice, 1495; trans. Rev. John M. Neale 1851):
O wondrous type, O vision fair / of glory that the Church shall share / Which Christ upon the mountain shows / where brighter than the sun He glows / With shining face and bright array / Christ deigns to manifest today / What glory shall be theirs above / who joy in God with perfect love.
Pope Saint Gregory the Great wrote of people by whom, "while still living in this corruptible flesh, yet growing in incalculable power by a certain piercingness of contemplation, the Eternal Brightness is able to be seen." In his poem The Book of the Twelve Béguines, John of Ruysbroeck, a 14th-century Flemish mystic beatified by Pope Pius X in 1908, wrote of "the uncreated Light, which is not God, but is the intermediary between Him and the 'seeing thought'" as illuminating the contemplative not in the highest mode of contemplation, but in the second of the four ascending modes.
The theological interpretation of Tabor's light came to be seen by anti-ecumenical currents of Eastern Orthodoxy as a major dogmatic division between the eastern and the western Church, with the Hesychast movement even described as "a direct condemnation of Papism".
Nevertheless, Roman Catholicism in recent years has shown itself more open to ideas of Hesychasm. Pope John Paul II repeatedly emphasized his respect for Eastern theology as an enrichment for the whole Church. John Paul II also named the Transfiguration as the fourth Luminous Mystery of the Holy Rosary. The Eastern doctrine of "uncreated light" has not been officially accepted in the Roman Catholic Church, which likewise has not officially condemned it. Increasing parts of the Western Church consider Gregory Palamas a saint, even if uncanonized. "Several Western scholars contend that the teaching of St. Gregory Palamas himself is compatible with Roman Catholic thought on the matter."
- John Meyendorff, "Mount Athos in the Fourteenth Century: Spiritual and Intellectual Legacy" in Dumbarton Oaks Papers 1988
- R.M. French, Foreword to Nicolaus Cabasilas, Joan Mervyn Hussey, P. A. McNulty (editors), A Commentary on the Divine Liturgy (St Vladimir's Seminary Press 1974 ISBN 978-0-913836-37-8), p. x
- Metamorphosis: The Transfiguration in Byzantine Theology and Iconography (St Vladimir's Seminary Press 2005, ISBN 0-88141-295-3), pp. 215-216
- Pope John Paul II and the East Pope John Paul II. "Eastern Theology Has Enriched the Whole Church" (11 August 1996). English translation
- Original text (in Italian)
- Seco, Lucas F. Mateo; Maspero, Giulio (2009). The Brill Dictionary of Gregory of Nyssa. Brill. p. 382.
- Uncreated Energies The understanding of heaven and "punishment" [hell] in historic Christianity is inextricably linked to the biblical concept of the Uncreated Light of God. The Uncreated Energies (or "Light" the purest form of energy) are understood by the Orthodox to be the Energies of God. This Energy is the "consuming fire", the Shechinah glory, the fire that burns gold to purify it, as St. Paul writes. It is the fire that burns the weeds left in the field, the fire that burns the pruned branches, it is the lake of divine fire, and the thirst and burning that torments the Rich Man is this same Uncreated Energy. Yet, the same fire that torments the impure gives warmth and comfort to the pure of heart. In fact, the Greek word "energeia", and its various forms, appears over 30 times in the new Testament, yet it is not translated as "energy" even once in most popular English translations. It is variously rendered as operation, strong, do, in-working, effectual, be mighty in, shew forth self, and even simply dropped out of the sentence; everything except what it means. Yet, this word was well established in the Greek language in the first century. It was first used by Aristotle, some three centuries before Christ, as a noun, as "energy" in the metaphysical sense – which was borrowed in recent years in English as an engineering term. But even in a modern metaphysical sense, it is exactly as the ancient Greeks use the word, because it is the same word. Yet the translators insisted on ignoring how this word is actually used by Greek speakers and distorted it into a number of verbs and adjectives (or simply drop it from the verse), which leaves only confusion and misunderstanding for English readers. When we are energized by the Divine Energies, we will radiate the pure Light of God. Translating directly from the Greek, Saint Paul writes to the Philippians [2:13] "For it is God who is energizing in you, according to His will and to energize for the sake of His being well-pleased." In verse 3:21 he further writes "[Christ] who will change the appearance of our humble bodies to take on the form of the body of His glory, through the energization of his Power…" And to the Ephesians in verse 1:19 "and what exceeding greatness of his power, in us who believe, through the energization of His mighty strength, energized in Christ, raising him from the dead and seating him in the right hand of Him in the heavens" So this energy "in us" changes our bodies to glory, and was the same energy that raised Christ from the dead. This energy is in fact, the Grace of God, in Eph 3:7 St. Paul writes "That I was made an attendant through the gift of the Grace of God, granted to me by the energization of his Power". This same Energy also has the power to heal, as St. James writes [5:16] "Therefore, confess your sins to one another, and pray for one another, so that you may be healed, prayers energized by a righteous one are very powerful". This same energy comes from the "one" that restrains evil, in II Thess 2:7 St. Paul writes "For already the mysterious lawless one is only restrained now by the Energies, until he comes out of the midst of it" Receiving this Divine Energy is the results of faith in the true God, as St. Paul tells the Thessalonians in I Thess 2:12 "…[you received] …the true Logos of God, which also energizes in you believers". Moreover, to the Galatians he asks a rhetorical question with an obvious answer [3:5] "Indeed, would it not be in vain, if the One providing you the Spirit and the powerful Energies in you, were by works of the law, or rather by hearing in faith?" Heaven & Hell in the Afterlife, According to the Bible By Peter Chopelas introduction by Thomas Hopko 
- PARADISE AND HELL IN THE ORTHODOX TRADITION by FR. GEORGE METALLINOS 
- Besides, we know from the whole teaching of the Church that God's uncreated grace takes different names according to the effects which its work has. If it purifies a person it is called purifying, if it illuminates it is called illuminating, if it deifies it is called deifying. Likewise sometimes it is described as bestowing being, sometimes as life-giving and sometimes as making wise. So all creation partakes of the uncreated grace of God, but differently. And therefore the deifying grace of which the saints partake should not be confused with other energies. The same thing is true of the grace of God in the eternal life. The righteous will share the illuminative and deifying energy, while the sinners and unpurified will experience the caustic and punishing energy of God. We find this teaching also in the ascetic writings of various saints. For example, St. John of the Ladder says that the same fire is called both "that which consumes and that which illuminates". He is referring to the holy and supracelestial fire which is the grace of God. The grace of God which men receive in this life "burns some because they still lack purification", and others "it enlightens in proportion to the perfection which they have achieved"22. Indeed, the grace of God does not purify unrepentant sinners in the next life, but what St. John of the Ladder says applies now. And it is testified by ascetic experience that at first the saints feel the grace of God as a fire which burns their passions, and afterwards, to the extent that their heart is purified, they also feel the grace of God as light. Contemporary men who see God on their ascetic pilgrimage affirm that as far as one repents and in grace experiences Hell, to that extent also grace, even without one's expecting it, is turned into uncreated light. It is the same grace of God which at first purifies the man, and when he reaches a great depth of repentance and purification, it is seen as light. Consequently, it is not a question of created things and human emotional states, but of experience of the uncreated grace of God. Life after Death by Metropolitan Hierotheos (Vlachos) of Nafpaktos
- Iōannēs Polemēs, Theophanes of Nicaea: His Life and Works, vol. 20 (Verlag der Österreichischen Akademie der Wissenschaften, 1996), p. 99
- Iōannēs Polemēs,Theophanes of Nicaea: His Life and Works, vol. 20 (Verlag der Österreichischen Akademie der Wissenschaften, 1996), p. 100
- Gregory the Great, Moralia, book 18, 89
- John Francis's translation of Jan van Ruysbroeck, The Book of the Twelve Béguines (John M. Watkins 1913), p. 40
- Orthodox Tradition."St. Gregory Palamas and the Pope of Rome", Volume XIII, Number 2.
- The "Luminous Mysteries", published in Rosarium Virginis Mariae, October 2002.
- Jaroslav Pelikan in John Meyendorff (editor), Gregory Palamas, The Triads, p. xi
- Michael J. Christensen, Jeffery A. Wittung (editors), Partakers of the Divine Nature (Associated University Presses 2007 ISBN 0-8386-4111-3), p. 243
- Lowell Clucas, 'The Triumph of Mysticism in Byzantium in the Fourteenth Century', in: Byzantine Studies in Honor of Milton V. Anastos, Byzantina kai Metabyzantina, ed. Speros Vryonis jr, Malibu (1985). 
- Vladimir Lossky, The Mystical Theology of the Eastern Church, SVS Press, 1997. (ISBN 0-913836-31-1) James Clarke & Co Ltd, 1991. (ISBN 0-227-67919-9)
- George S. Maloney, A Theology of Uncreated Energies of God (1978), ISBN 978-0-87462-516-5.
- George C. Papademetriou, Introduction to Saint Gregory Palamas (2005), ISBN 978-1-885652-83-6.
- J. Meyendorff, A Study of St. Gregory Palamas (1959).
- Andreas Andreopoulos, Metamorphosis: The Transfiguration in Byzantine Theology and Iconography SVS Press, 2005 (ISBN 0-88141-295-3).
- Light in Icon (Russia-hc.ru)
- The Sunday of St. Gregory Palamas (The Second Sunday of Great and Holy Lent) by Benedict Seraphim
- Theoria, Tabor Light (photismos) as Vision