The Transfiguration of Our Lord. A Manifestation of God’s Glory that gave the Apostles Peter, James and John not only a Glimpse of Our Lord Jesus Christ’s Divine Beauty, but also the Strength they were to Need for all the Trials to come.
When You were transfigured, O Savior, upon a high mountain, having with You the chief disciples, You shone forth in glorious majesty, proving thereby that those who surpass in the height of their virtues shall be counted worthy of the divine glory. Talking with Christ, Moses and Elijah showed that He is the Lord of both the living and the dead, the God who spoke of old through the Law and the Prophets. And the voice of the Father testified to Him from the cloud of light saying, “Hear Him, who through His Cross destroys hell and gives the dead eternal life.”
Having uncovered, O Savior, a little of the light of Your divinity to those who went up with You into the mountain, You have made them lovers of Your heavenly glory. Therefore they cried in awe: “It is good for us to be here. With them we all we sing unto You…
The Transfiguration of Christ is one of the central events recorded in the Gospels. Immediately after the Lord was recognized by His disciples as the Christ, the Son of the Living God, he told them that He must go up to Jerusalem and suffer many things… and be killed and on the third day be raised. This announcement of Christ’s approaching passion and death was met with indignation by the disciples. And then, after rebuking them, the Lord took Peter, James, and John up to a high mountain, by tradition Mount Tabor, and was transfigured before them.
In the Transfiguration, the disciples see the glory of the Kingdom of God present in majesty in the Person of Christ. They see that in Him, all the fullness of God was pleased to dwell. They see this before the crucifixion so that in the resurrection they might know who it is Who has suffered for them, and what it is that this One, who is God, has prepared for those who love Him.
Besides this meaning, the presence of Moses and Elijah is also of great significance for understanding of the feast. These two figures actually stand for the Old Testament itself: MOSES for the LAW, and ELIJAH for the PROPHETS. They also stand for the LIVING and DEAD, for Moses died and his burial place is known, while Elijah was taken alive into heaven in order to appear again to announce the time of God s salvation in Christ the Messiah. Christ is the Lord of both the living and the dead (Bold face added by FTP for Emphasis).
Taken from The Orthodox Faith, Vol. II, by Fr. Thomas Hopko (Theologic.com).
I have chosen the quote from “The Orthodox Faith” not only because of its Lovely Prayer at the beginning, but more so for the last paragraph. It beautifully points out the significance of the presence of both Moses and Elijah.
Following is a quick and easy read that also explains the Feast of the Transfiguration of Our Lord:
Our divine Redeemer, being in Galilee about a year before His sacred Passion, took with him St. Peter and the two sons of Zebedee, Sts. James and John, and led them to a retired mountain. Tradition assures us that this was Mount Thabor, which is exceedingly high and beautiful, and was anciently covered with green trees and shrubs, and was very fruitful. It rises something like a sugar-loaf, in a vast plain in the middle of Galilee. This was the place in which the Man-God appeared in His glory.
Whilst Jesus prayed, he suffered that glory which was always due to his sacred humility, and of which, for our sake, He deprived it, to diffuse a ray over His whole body. His face was altered and shone as the sun, and his garments became white as snow. Moses and Elias were seen by the three apostles in his company on this occasion, and were heard discoursing with him of the death which he was to suffer in Jerusalem.
The three apostles were wonderfully delighted with this glorious vision, and St. Peter cried out to Christ, “Lord, it is good for us to be here. Let us make three tents: one for thee, one for Moses, and one for Elias” Whilst St. Peter was speaking, there came, on a sudden, a bright shining cloud from heaven, an emblem of the presence of God’s majesty, and from out of this cloud was heard a voice which said, “This is my beloved Son, in whom I am well pleased; hear ye him” The apostles that were present, upon hearing this voice, were seized with a sudden fear, and fell upon the ground; but Jesus, going to them, touched them, and bade them to rise. They immediately did so, and saw no one but Jesus standing in his ordinary state.
Excerpted from Butler’s Lives of the Saints, Benziger Bros. ed. 
In the Transfiguration Christ enjoyed for a short while that glorified state which was to be permanently His after His Resurrection on Easter Sunday. The splendor of His inward Divinity and of the Beatific Vision of His soul overflowed on His body, and permeated His garments so that Christ stood before Peter, James, and John in a snow-white brightness. The purpose of the Transfiguration was to encourage and strengthen the Apostles who were depressed by their Master’s prediction of His own Passion and Death. The Apostles were made to understand that His redeeming work has two phases: The Cross, and glory—that we shall be glorified with Him only if we first suffer with Him.
— Rt. Rev. Msgr. Rudolph G. Bandas (Catholic.org)
First I wanted to be sure and Honor the day with its significance and meaning.
The Transfiguration of Our Lord has always been a very memorable Feast Day for me. I love the Iconography of the Transfiguration. It has always fascinated me. The visual representations are Beautiful! Brilliant! Memorable. But what has ALWAYS stood out at me is the Gospel of Luke in regards to the event:
28About eight days after Jesus said this, he took Peter, John and James with him and went up onto a mountain to pray. 29As he was praying, the appearance of his face changed, and his clothes became as bright as a flash of lightning. 30Two men, Moses and Elijah, 31appeared in glorious splendor, talking with Jesus. They spoke about his departure, which he was about to bring to fulfillment at Jerusalem. 32Peter and his companions were very sleepy, but when they became fully awake, they saw his glory and the two men standing with him. 33As the men were leaving Jesus, Peter said to him, “Master, it is good for us to be here. Let us put up three shelters—one for you, one for Moses and one for Elijah.” (He did not know what he was saying.) [Bold face added by FTP for emphasis]
~ Luke 9:28-33
Okay, so maybe no one else will find this funny, but I have always laughed at this line! I mean was Luke Hating on Peter? None of the other Gospels have, well what shall I call it, an aside? Maybe my perception is all wrong. Maybe he wasn’t hating. Maybe he’s just Clarifying for the rest of us. But come on, Isn’t it FUNNY?