Many people believe in a common rumour that John the Baptist is Elijah reincarnated because of a misinterpreted verse in the Bible. However, it is likely not the case.
John the Baptizer demonstrated the vigorous drive and energetic zeal that Elijah had shown, and this resulted in John having a powerful effect on his listeners; he could have been said to have gone forth " with Elijah's spirit and power. Luke 1:17
What is likely?