Six days later Jesus took Peter and the two brothers, James and John, and led them up a high mountain.
As the men watched, Jesus' appearance changed so that his face shone like the sun, and his clothing became dazzling white.
Suddenly, Moses and Elijah appeared and began talking with Jesus.
Peter blurted out, "Lord, this is wonderful! If you want me to, I'll make three shrines, one for you, one for Moses, and one for Elijah."
But even as he said it, a bright cloud came over them, and a voice from the cloud said, "This is my beloved Son, and I am fully pleased with him. Listen to him."
The disciples were terrified and fell face down on the ground.
Jesus came over and touched them. "Get up," he said, "don't be afraid."
And when they looked, they saw only Jesus with them.
As they descended the mountain, Jesus commanded them, "Don't tell anyone what you have seen until I, the Son of Man, have been raised from the dead."
His disciples asked, "Why do the teachers of religious law insist that Elijah must return before the Messiah comes?"
Jesus replied, "Elijah is indeed coming first to set everything in order.
But I tell you, he has already come, but he wasn't recognized, and he was badly mistreated. And soon the Son of Man will also suffer at their hands."
Then the disciples realized he had been speaking of John the Baptist.
When they arrived at the foot of the mountain, a huge crowd was waiting for them. A man came and knelt before Jesus and said,
"Lord, have mercy on my son, because he has seizures and suffers terribly. He often falls into the fire or into the water.
So I brought him to your disciples, but they couldn't heal him."
Jesus replied, "You stubborn, faithless people! How long must I be with you until you believe? How long must I put up with you? Bring the boy to me."
Then Jesus rebuked the demon in the boy, and it left him. From that moment the boy was well.
Afterward the disciples asked Jesus privately, "Why couldn't we cast out that demon?"
"You didn't have enough faith," Jesus told them. "I assure you, even if you had faith as small as a mustard seed you could say to this mountain, 'Move from here to there,' and it would move. Nothing would be impossible."