At that time, Jesus took with him Peter and John and James, and went up on the mountain to pray. And as he was praying, the appearance of his countenance was altered, and his raiment became dazzling white.
And behold, two men talked with him, Moses and Elijah, who appeared in glory and spoke of his departure, which he was to accomplish at Jerusalem.
Now Peter and those who were with him were heavy with sleep, and when they wakened they saw his glory and the two men who stood with him.
And as the men were parting from him, Peter said to Jesus, “Master, it is well that we are here; let us make three booths, one for you and one for Moses and one for Elijah” – not knowing what he said.
As he said this, a cloud came and overshadowed them; and they were afraid as they entered the cloud. And a voice came out of the cloud, saying, “This is my Son, my Beloved; listen to him!”
And when the voice had spoken, Jesus was found alone.
And they kept silence and told no one in those days anything of what they had seen.
St. Peter’s Second Universal Letter 1:10-19
BRETHREN, be more zealous to confirm your call and election, for if you do this you will never fall; so there will be richly provided for you an entrance into the eternal kingdom of our Lord and Savior Jesus Christ.
Therefore I intend always to remind you of these things, though you know them and are established in the truth that you have. I think it right, as long as I am in this body, to arouse you by way of reminder, since I know that the putting off of my body will be soon, as our Lord Jesus Christ showed me. And I will see to it that after my departure you may be able at any time to recall these things.
For we did not follow cleverly devised myths when we made known to you the power and coming of our Lord Jesus Christ, but we were eyewitnesses of his majesty.
For when he received honor and glory from God the Father and the voice was borne to him by the Majestic Glory, “This is my beloved Son, with whom I am well pleased,” we heard this voice borne from heaven, for we were with him on the holy mountain.
And we have the prophetic word made more sure.
You will do well to pay attention to this as to a lamp shining in a dark place, until the day dawns and the morning star rises in your hearts.
At that time, Jesus took with him Peter and James and John his brother, and led them up a high mountain apart.
And he was transfigured before them, and his face shone like the sun, and his garments became white as light.
And behold, there appeared to them Moses and Elijah, talking with him.
And Peter said to Jesus, “Lord, it is well that we are here; if you wish, I will make three booths here, one for you and one for Moses and one for Elijah.”
He was still speaking, when lo, a bright cloud overshadowed them, and a voice from the cloud said, “This is my beloved Son, with whom I am well pleased; listen to him.”
When the disciples heard this, they fell on their faces, and were filled with awe.
But Jesus came and touched them, saying, “Rise, and have no fear.” And when they lifted 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 raised from the dead.”