After six days Jesus took with him Peter, James and John the brother of James, and led them up a high mountain by themselves.
References for Matthew 17:1
There he was transfigured before them. His face shone like the sun, and his clothes became as white as the light.
Just then there appeared before them Moses and Elijah, talking with Jesus.
Peter said to Jesus, “Lord, it is good for us to be here. If you wish, I will put up three shelters—one for you, one for Moses and one for Elijah.”
While he was still speaking, a bright cloud covered them, and a voice from the cloud said, “This is my Son, whom I love; with him I am well pleased. Listen to him!”
References for Matthew 17:5