Recently I was struck by a passage I've previously read hundreds of times while praying the Luminous Mysteries using the scriptural Rosary program I downloaded a couple of years ago: "They spoke of Jesus' exodus that he was going to accomplish in Jerusalem." (Lk 9:31 RSV-Catholic Edition)
I've never before noticed the word "exodus." Nor, for that matter, paid much attention to any speaking other than the voice from the cloud; when I think of the Transfiguration, I think of the visual event, the sudden appearance of Moses and Elijah, the dazzling white clothing of Jesus. Peter and the other two disciples saw his glory (Lk 9:32).
I've understood the Transfiguration to be foretelling Christ's Passion and death (not that I paid much attention to it before I became Catholic). That much we learn from Jesus' telling these closest disciples, as they came down the mountain together, that the Son of man was to rise from the dead.
The passage in Luke, though, unlike the parallel accounts in Matthew 17 and Mark 9, mentions (however enigmatically) the content of what Moses and Elijah had to say. Exodus symbolizes salvation, I noticed today in a footnote in Peter Kreeft's Summa of the Summa. I'm still puzzled by the significance of the word. The RSV (non-Catholic edition) says Moses and Elijah "appeared in glory and spoke of his departure which he was to accomplish at Jerusalem." Departure, exodus--why is the latter considered more fitting?