Do you remember what happened when your parents first met the person who eventually became your spouse? Probably they weren't too impressed. Later, when you were alone with them, you tried to explain why he or she was so special. You had experienced things about and with this individual which most people, at first glance, had never noticed; things which not only attracted you, but if you followed through on your insights, could change your life.
The first disciples of the historical Jesus faced the same problem. Most of the inhabitants of Capernaum saw only the town carpenter when Jesus crossed their path. Probably they talked only about "carpenter stuff" during their brief encounters. Yet the small handful who had heard him talk about God's kingdom among them, who had seen how he related to the unfortunates on society's perimeter, experienced something in Jesus that others never noticed. They also knew that what they experienced could change the way they lived their lives.
Like all of us, they would have put their experiences of Jesus into categories with which they were familiar. Being Jews, they reflected on their Scriptures, surfacing ideas which demonstrated how he was the one who fulfilled many of the dreams they shared; dreams of God and the Messiah working among the Chosen People, bringing the kind of life they longed for.
That's why Moses and Elijah are always included in transfiguration narratives. In Scripture, the Bible is never called the Bible. It's simply referred to as "the law and the prophets." In this situation, Moses represents the law, Elijah the prophets. Their appearance demonstrates that the only way to understand Jesus is within the context of the Scriptures on which he based his reform.
His disciples also realized Jesus was going to usher in a new era, the time all Jews anticipate every fall when they participate in the fest of Booths. The celebration shows their belief that one day Yahweh will again come among them, as Yahweh had done during their wandering in the wilderness. When that happens, they will return to living in tents or booths as their ancestors had for 40 years. That's why Peter talks about setting up three tents. He's really saying, "What we expect in the future is actually happening now!"
These initial disciples also found Daniel's well-known "Son of Man" pericope helpful in understanding Jesus. As Alexander Di Lella states in the New Jerome Biblical Commentary, the original apocalyptic writer of this book probably intended the one "coming on the clouds of heaven" to be a symbol of God's kingdom. "However, because in Daniel the thought of 'kingdom' often shifts imperceptibly into that of 'king,' the concept of the 'son of man' eventually shifted from a figure of speech for the theocratic kingdom into a term for the messianic king himself." That's exactly how the authors of the Christian Scriptures interpreted the phrase.
On the other hand, we must be careful how we interpret II Peter's comment, ". . . We did not follow cleverly devised myths . . . ." Though the experience of perceiving Jesus' real personality wasn't a myth, all Scripture scholars agree that Mark used mythic concepts in his description of that insight.
One last point. The CBS Evening News practice of daily highlighting one of our military killed in Iraq or Afghanistan bothers me a little. Had these individuals not died, probably few people would have reflected on their personalities deeply enough to surface the outstanding characteristics profiled in those brief segments. In the same way, had Jesus not died and rose, few of his contemporaries would have noticed the qualities in him that our sacred authors have passed on to us.