Then the three disciples saw Elijah and Moses talking with Jesus.

The LORD Almighty answers, "I will send my messenger to prepare the way for me. Then the Lord you are looking for will suddenly come to his Temple. The messenger you long to see will come and proclaim my covenant."

"But before the great and terrible day of the LORD comes, I will send you the prophet Elijah.

and if you are willing to believe their message, John is Elijah, whose coming was predicted.

Then the disciples asked Jesus, "Why do the teachers of the Law say that Elijah has to come first?"

"Elijah is indeed coming first," answered Jesus, "and he will get everything ready.