Matthew 17:10-13

His disciples asked Him, “Why then do the scribes say that Elijah must come first?” Jesus answered, “Elijah truly does first come and will restore all things. But I tell you that Elijah has already come, and they did not know him, but did to him whatever they pleased. Likewise, the Son of Man will also suffer at their hands.” Then the disciples understood that He was speaking to them of John the Baptist.