Matthew 17:12 in the King James Version
But I say unto you, That Elias is come already, and they knew him not, but have done unto him whatsoever they listed. Likewise shall also the Son of man suffer of them.
Context
11 Jesus answered them, “Elijah indeed comes first, and will restore all things;
12 but I tell you that Elijah has come already, and they didn’t recognize him, but did to him whatever they wanted to. Even so the Son of Man will also suffer by them.”
13 Then the disciples understood that he spoke to them of John the Baptizer.