Mark 9:10 (KJV)

And Peter answered and said to Jesus, Master, it is good for us to be here: and let us make three tabernacles; one for thee, and one for Moses, and one for Elias.

For he wist not what to say; for they were sore afraid.

And there was a cloud that overshadowed them: and a voice came out of the cloud, saying, This is my beloved Son: hear him.

And suddenly, when they had looked round about, they saw no man any more, save Jesus only with themselves.

And as they came down from the mountain, he charged them that they should tell no man what things they had seen, till the Son of man were risen from the dead.

And they asked him, saying, Why say the scribes that Elias must first come?

And he answered and told them, Elias verily cometh first, and restoreth all things; and how it is written of the Son of man, that he must suffer many things, and be set at nought.

But I say unto you, That Elias is indeed come, and they have done unto him whatsoever they listed, as it is written of him.

And when he came to his disciples, he saw a great multitude about them, and the scribes questioning with them.

And straightway all the people, when they beheld him, were greatly amazed, and running to him saluted him.