Mark 9:8

Peter answered Jesus, “Rabbi, it is good for us to be here. Let’s make three tents: one for you, one for Moses, and one for Elijah.”

For he didn’t know what to say, for they were very afraid.

A cloud came, overshadowing them, and a voice came out of the cloud, “This is my beloved Son. Listen to him.”

As they were coming down from the mountain, he commanded them that they should tell no one what things they had seen, until after the Son of Man had risen from the dead.

They kept this saying to themselves, questioning what the “rising from the dead” meant.

They asked him, saying, “Why do the scribes say that Elijah must come first?”