The rest of this verse sheds light on what is meant here. “I am the Light of the world. He who follows me shall not walk in darkness, but have the light of life.” Here and in a number of other places, Jesus is portrayed as a Beacon: one who guides along a right path, who illumines the way for us. He is the “Giver of light,” the One bringing light to our hearts. To say that He is light in this way is to talk about what he does.
But there is another way to see Christ as light. He is light, not only because of what He does for us, but because of what He is. “God is light, and in Him is no darkness at all” (1 John 1:5). God is not described here as light illumining our minds or hearts, but as He is in Himself: Light in His innermost being.
Based on the Gospel message, the Church proclaims the Lord Jesus as “Light from Light” (Nicene Creed), the “Joyful Light of the holy glory of the immortal Father, the Heavenly, the Holy, the Blessed: Jesus Christ” (third-century Vespers hymn). As God is Light in Himself, so too the incarnate Christ is the Light of the Father. “I and the Father are one” (John 10:30).
As far back as the third century, the Fathers used our experience of the sun to illustrate this mystery. Like others before him, St Cyril, the ninth-century teacher of the Slavs, reflected, “Do you see in the heavens the brilliant sphere of the sun and how light is begotten and warmth proceeds from it? God the Father is like the sphere of the sun, without beginning or end. From Him is eternally begotten God the Son, like light from the sun; and just as there comes warmth together with light, the Holy Spirit proceeds. Each one is distinguished separately: the sphere of the sun, the light and the warmth – these are not three suns, but one sun in the heavens. So also, in the Holy Trinity: there are three Persons, but God is one and indivisible.”
The Light of Mt. Tabor
Christ was concretely manifested as light at His Transfiguration. “His face shone like the sun and His clothes became as white as light” (Matthew 17:2) – “white and glistening” (Luke 9:29), “such as no launderer on earth can whiten them” (Mark 9:3). For a moment, His disciples glimpsed what had been hidden since the Incarnation: the Word of God, radiant with divine glory, in the person of Jesus.In icons of the Transfiguration, this radiance is depicted by a geometric figure behind the representation of the Lord, called a mandorla. While depictions of Christ during His earthly ministry show His head surrounded by a cross and a halo, icons representing Him in moments beyond time and space (e.g. the Transfiguration, the Resurrection, the Dormition) envelop His whole body in this light of glory.
This same figure is found in icons of the conversion of St Paul. Christ, the “radiant Light” was manifested to Saul of Tarsus (St Paul) on the road to Damascus as “a light from the sky brighter than the sun” (Acts 26:13). While this light briefly blinded Saul by its brilliance, it ultimately enabled him to see even more clearly “the mystery which has been hidden from ages and from generations, but now has been revealed” (Colossians 1:26).
In the Church, the light experienced by Saul has been identified with the light that shone on Tabor, the Radiant Light of the Father, Jesus Christ. As we sing on the feast of Saints Peter and Paul, “Christ, who had been radiant in light on the mountain, blinded your bodily eyes; but He allowed your soul to see the Trinity” (from the canon, ode 1).
The “Uncreated Light” of God
In the Gospels we find two seemingly contradictory understandings of our ability to know God. On the one hand, we are told, “No one has seen God at any time” (John 1:18). On the other hand we hear, “Blessed are the pure in heart, for they shall see God” (Matthew 5:8). In the fourth century St Gregory of Nyssa showed how both statements are true.He taught that the essence of God was unknowable. Like the sun in the imagery cited above, God in His deepest being is unapproachable. The energies of God – His “Light” and “Warmth” – have been made known to us and we can truly know God in His energies.
In the fourteenth century, St Gregory Palamas applied this teaching to the Transfiguration. He explained that, when the Apostles witnessed the Transfiguration of the Lord on Mount Tabor, that they were seeing the actual uncreated light of God.
Reflecting the Divine Light
We too, Palamas insisted, can experience God’s divine energies even though we can never know His essence: “for those who love ech other, all nature is filled with the light which seems to radiate from the other.” Many saints who have loved deeply have reflected this light. Perhaps the first was the Protomartyr St Stephen, who witnessed to Christ before the council of Jewish elders in Jerusalem, “And looking steadfastly on Stephen, they saw his face as it had been the face of an angel” (Acts 6:15).St Simeon the New Theologian, writing in the eleventh century, described his own experience in similar words: “He gives Himself totally to me, unworthy as I am, and I am filled with His love and beauty. I am sated with pleasure and divine tenderness. I share in the Light. I participate also in the glory. My face shines like that of my beloved, and all my members become bearers of Light.”
The most compelling witness to such an experience comes from Nicholas Motovilov. In 1831 he wrote of seeing St Seraphim of Sarov transfigured with the divine light. They had been discussing how a person can acquire the grace of the Holy Spirit, but Motovilov was puzzled: “I do not understand how I can be certain that I am in the Spirit of God. Finally, as he described it, “Father Seraphim took me very firmly by the shoulders and said, ‘We are both in the Spirit of God now, my son. Why don’t you look at me?’” I replied, ‘I cannot look, Father, because your eyes are flashing like lightning. Your face has become brighter than the sun, and my eyes ache with pain.’
“Father Seraphim said, ‘Don’t be alarmed, Your Godliness! Now you yourself have become as bright as I am. You are now in the fullness of the Spirit of God yourself; otherwise, you would not be able to see me as I am.’
“Then, bending his head toward me, he whispered softly in my ear: ‘Thank the Lord God for His unutterable mercy to us. You saw that I did not even cross myself; only in my heart did I pray mentally to the Lord God and said within myself, ‘Lord, grant him to see clearly with his bodily eyes that descent of Your Spirit which You grant to Your servants when you are pleased to appear in the light of Your magnificent glory.’ And you see, my son, the Lord instantly fulfilled the humble prayer of poor Seraphim. How, then, shall we not thank Him for this unspeakable gift to us both!’”
For a moment the Apostles on Tabor saw the light of God which is Christ’s by nature. Likewise, for a moment Nicholas Motovilov saw the light of God indwelling by grace in the person who is in Christ.