Then a cloud appeared and covered them, and a voice came from the cloud: “This is my Son, whom I love. Listen to him!” (Mark 9:7).
The story of Jesus taking Peter, James and John to a high mountain where he is “transfigured” is found in the Gospels of Matthew, Mark, and Luke – and at exactly the same place: right after Peter confesses, on behalf of all the disciples, their faith that Jesus is the son of God.
Mark opens his gospel with the announcement that with the coming of Jesus, the Kingdom (or rule) of God has come near (1:15). This has a positive consequence for the believer as the next nine chapters unfold: There is no reason for the disciple of Jesus to fear in the misfortunes of life, nor the challenges that life may present nor the demonic powers who may present them. Jesus is superior to them all and ready to deliver.
But there are responsibilities: the disciple must not try to cram his discipleship into his old life. He must live a new life. Second, old rules and traditions must be jettisoned in favor of a new way of living, and that way must be lived according to the word of God. On the Mount of Transfiguration, for the third time in the book (see Mark 3:35; 7:1-13; and here), this point is made. In all three gospels the point is the same: those who confess Christ must do as He says. Put another way, the benefits of the Kingdom of God belong only to those who are subject to its king.