By Elder Sophrony Sakharov
The Apostles on Mount Tabor were found worthy to enter the realm of Light proceeding from the Father, and hear His voice bearing witness to His beloved Son. But this became possible for them only after they had confessed the Divinity of Christ [cf. Matt. 16:13].
It has been granted to me to contemplate different kinds of light and lights - the light the artist knows when elated by the beauty of the visible world; the light of philosophical contemplation that develops into a mystical experience. Let us even include the 'light' of scientific knowledge which is always and inevitably of very relative value. I have been tempted by manifestations of light from hostile spirits. But in my adult years, when I returned to Christ as perfect God, the unoriginate Light shone on me. This wondrous Light, even in the measure vouchsafed me from on High, ecliped all else, just as the rising sun eclipses the brightest star....
The action on man's spirit of the Light of which I write bears witness to its Divine Nature. It is uncreated, unnameable. It is mysterious, imponderable, inviolable. I do not know how to describe it. By nature it is otherworldly, supranatural. Its coming down to us is no less than the manifestation of God to man, the revelation of heavenly mysteries. By the gift of this Light at the Transfiguration on Mount Tabor was knowledge of God confirmed. From the moment it shone there on the three Apostles it entered into the history of our world, to become the inalienable inheritance of generation after generation of those who believe in Christ God. Without this Light the earth would have forever lacked true knowledge of God. Judging by my own experience I would call it the Light of resurrection. Its coming introduces the spirit into the sphere where there is no death. Without its irradiation it is impossible duly to apprehend the ways of salvation. The world - people - would remain in the darkness of ignorance. Even the most exquisite abstract theological formation does not mean salvation since it merely provides intellectual understanding without lifting one to the realm of Divine Being....
Manifestations of Light, which is unique in its eternal nature, differs both in degree of energy and mode. Rarely in the history of the Church have visions of Light attained such fullness that the visionary is also vouchsafed a personal revelation. This did happen on Mount Tabor when Peter, James and John heard the Father's "voice out of the cloud" bearing witness to His beloved Son. So it was with the Apostle Paul on the road to Damascus - "And suddenly there shined round him a light from heaven," - followed by personal converse with Christ, Who assured Paul that He was the God Whom he revered, Who had manifest Himself to Moses on Sinai. "I am Jesus whom thou persecutest" [Acts 9:5].
From the book We Shall See Him As He Is, Ch. 12.