Mark 9:9-13
9 As they were coming down the mountain, Jesus gave them orders not to tell anyone what they had seen until the Son of Man had risen from the dead. 10 They kept the matter to themselves, discussing what “rising from the dead” meant.
11 And they asked him, “Why do the teachers of the law say that Elijah must come first?”
12 Jesus replied, “To be sure, Elijah does come first, and restores all things. Why then is it written that the Son of Man must suffer much and be rejected? 13 But I tell you, Elijah has come, and they have done to him everything they wished, just as it is written about him.”