What does Luke 9:32 mean?
When Jesus ministers to crowds, He often doesn't have time to eat, let alone sleep. The disciples discovered how draining this could be (Mark 6:30–31). But Jesus values prayer more than sleep and makes it a priority (Mark 1:35)—an occasional nap in a storm notwithstanding (Luke 8:22–23). The disciples are not so disciplined, as the incident in the garden of Gethsemane proves (Luke 22:39–46), although there is no indication here that Jesus told them to stay awake and pray.And so, while Jesus prays, the trio have fallen asleep. When they awaken, everything has changed.
Jesus does not look like Himself. He is not grimy and weary with travel. His clothes glow so brightly they flash like lightning (Luke 9:29, AMP). His face shines like the sun (Matthew 17:2). He is speaking to two men who also shine with otherworldly glory. Somehow, the three men recognize two pillars of their nation's history: Moses and Elijah. Jesus and the Old Testament saints are talking about Jesus' departure, or exodos, from Jerusalem (Luke 9:28–31).
Faced with these notable figures, Peter offers to make three tents for them. This is the wrong thing to say. Perhaps he is inferring that Jesus, Moses, and Elijah are on equal terms. If Jesus were only a human teacher, this would be an act of honor. But Jesus isn't just a human teacher (Luke 9:33). Or perhaps Peter is failing to grasp the magnitude of the situation. Moses and Elijah are not meant to stay. Jesus' ministry on earth is not merely a continuation of the old; He brings the fulfillment of the old and something new. Or Peter may simply be so stunned he is unsure what to do, and offering shelter so the men can remain is his instinctive reaction.
The shekinah glory of God descends on the mountain like a thick cloud. Peter joins James and John in silence as the cloud envelops them. God's voice thunders, "This is my Son, my Chosen One; listen to him!" (Luke 9:34–35).
Jesus is not "just" a teacher. This is not a mere king who will conquer the Roman occupiers and return freedom to the Jews. If so, He would be equal to Moses and Elijah and Peter's offer would be appropriate. But this is the Son of God and the Messiah; the three disciples need to listen to everything He says.