Prior to ascending the mountain, Christ had asked all of his disciples: “Who are men saying that I am?” whereupon Peter replied: “You are the Christ.” At that Jesus told them that he would die and be resurrected (Mr 8:27-31), though he also promised that some of his disciples would “not taste death at all” until they had first seen “the Son of man coming in his kingdom,” or “the kingdom of God already come in power.” (Mt 16:28; Mr 9:1) This promise was fulfilled “six days later” (or “eight” according to Luke, who apparently includes the day of the promise and that of the fulfillment) when Peter, James, and John accompanied Jesus into “a lofty mountain” (Mt 17:1; Mr 9:2; Lu 9:28) where, while praying, Jesus was transfigured before them.

The apostle Peter viewed the transfiguration as a marvelous confirmation of the prophetic word, and by having been an eyewitness of Christ’s magnificence, he was able to acquaint his readers “with the power and presence of our Lord Jesus Christ.” (2Pe 1:16, 19) The apostle had experienced the fulfillment of Christ’s promise that some of his followers would “not taste death at all until first they see the kingdom of God already come in power.” (Mr 9:1) The apostle John may also have alluded to the transfiguration at John 1:14.