Mark 8:28

8:28 They said, “John the Baptist, others say Elijah, and still others, one of the prophets.”

Mark 9:12-13

9:12 He said to them, “Elijah does indeed come first, and restores all things. And why is it written that the Son of Man must suffer many things and be despised? 9:13 But I tell you that Elijah has certainly come, and they did to him whatever they wanted, just as it is written about him.”

Mark 15:35-36

15:35 When some of the bystanders heard it they said, “Listen, he is calling for Elijah!” 15:36 Then someone ran, filled a sponge with sour wine, put it on a stick, and gave it to him to drink, saying, “Leave him alone! Let’s see if Elijah will come to take him down!”

Malachi 4:5

4:5 Look, I will send you Elijah the prophet before the great and terrible day of the Lord arrives.