Gospel of the Sunday (Matthew 17:1–9)
At that time Jesus took Peter, James, and his brother John and led them up a high mountain by themselves. And He was transfigured before them. His face shone like the sun, and His garments became white as light.
And behold, there appeared to them Moses and Elijah, speaking with Him. Peter said to Jesus: Lord, it is good that we are here. If You will, let us make three tents here: one for You, one for Moses, and one for Elijah.
While he was still speaking, a bright cloud overshadowed them, and a voice from the cloud said: This is My beloved Son, in whom I am well pleased; listen to Him.
When the disciples heard this, they fell on their faces and were afraid. But Jesus came and touched them, saying: Rise, and do not be afraid. And lifting up their eyes, they saw no one but Jesus only.
And as they were coming down the mountain, Jesus commanded them: Tell no one the vision, until the Son of Man is risen from the dead.
Sermon of St Leo the Great on the Transfiguration
The Lord revealed before chosen witnesses the glory of His majesty and illumined the body which He shared with the rest of mankind with such splendor that His face shone like the sun and His garments became white as snow.
This Transfiguration was chiefly intended to remove the scandal of the Cross from the hearts of His disciples, so that the humiliation of His voluntary Passion might not shake their faith, since they had already beheld the exaltation of His hidden dignity. At the same time a firm hope was laid for the holy Church, that the whole body of Christ might understand to what glory it is called, seeing that the Head already shines with such radiance.
The Lord had shortly before declared that some standing there would not taste death before they had seen the Son of Man coming in His kingdom. Therefore He took Peter, James, and John, led them up a high mountain, and showed them the glory of His divine nature.
Moses and Elijah appeared and spoke with Him, showing that the Law and the Prophets find their fulfillment in Christ. In Him all is brought to completion.
When Peter said, Lord, it is good that we are here, he spoke out of love, yet did not fully understand that the path to glory passes through suffering. The world could not be redeemed without the Cross.
From the cloud came the voice of the Father: This is My beloved Son; listen to Him. Thus all doubt is removed. He is not adopted but begotten; not created but born; one in essence with the Father.
When the disciples fell to the ground, Jesus raised them and said: Rise, and do not be afraid. He strengthened their faith so that, after the Passion, they might proclaim His glory without scandal.
In this revelation the hope of the Church is founded. Whoever shares in the sufferings of Christ shall also share in His glory.