Mark 9:9-13

And as they were coming down from the mountain, he charged them that they should tell no man what things they had seen, save when the Son of man should have risen again from the dead. And they kept the saying, questioning among themselves what the rising again from the dead should mean. And they asked him, saying, How is it that the scribes say that Elijah must first come? And he said unto them, Elijah indeed cometh first, and restoreth all things: and how is it written of the Son of man, that he should suffer many things and be set at nought? But I say unto you, that Elijah is come, and they have also done unto him whatsoever they would, even as it is written of him.