, Mark 9:2–8, Luke 9:28–36)) tells the story of when Jesus and three of his apostles -- Peter, James and John -- climb a mountain (traditionally held to be Mount Tabor in lower Galilee, Israel) in order to pray. There, Jesus begins to shine with bright rays of light. He is then joined by Moses and Elijah and a voice from the sky (presumably God's) calls him Son. As our pastor recently noted during worship, the story is so embellished with symbols, metaphors, and literary allusions, it's hard to take seriously. It's not believable.
That said, many people have had Mountain Top experiences, moments in their lives when the Divine breaks into our midst and sometimes leaves us breathless (New Testament scholar Marcus Borg once wrote about such an experience although I don't think it occurred on a mountain top). Since there is no reason to suppose that Jesus, Peter, James, and John were incapable of experiencing such a moment, the fact that over time the story about their experience took on increasingly unbelievable elements, doesn't mean that it didn't happen.