Question:
Are Elijah and John the Baptist the same person?

Answer:
The Scriptures are clear that John was sent in the spirit and power of Elijah. It is also clear from John 1:21 that John was not actually Elijah, for when asked if he was Elijah, he replied, “I am not.”

But in Luke 1:17 the angel who appeared to Zacharias informed him that the son who would be born to him and Elisabeth would “go before Him [the Lord] in the spirit and power of Elijah.” The angel went on to say that John would “turn the hearts of the fathers to the children,” and this matches perfectly with Malachi’s closing words, “Behold, I will send you Elijah the prophet before the coming of the great and dreadful day of the Lord: and he shall turn the heart of the fathers to the children” (Malachi 4:5, 6). So then, though John was not the “literal” Elijah, he was the one who would answer to the prophecies of Malachi and the angel Gabriel.
We might ask ourselves at this point, “What does `the spirit and power of Elijah’ mean?” To answer this, we must think back to the life of Elijah. Elijah lived at a time of great apostasy. The children of Israel had departed from their worship of Jehovah and become idolaters. Elijah was raised up of God to recall the people back to Jehovah, to bring them to true repentance. In order to do this, Elijah needed to be all-out for God. He needed to have God’s thoughts regarding His people and he needed to have the moral and spiritual power to bring them to repentance. Now think of John. He, too, lived in a time of great spiritual declension. John was also raised up of God to point the people to their sins and to bring them to true repentance. And he would need, like Elijah, great spiritual energy to bring this about. We know that John was a fiery preacher who, no doubt, commanded the respect of his listeners because his life was fully consecrated to God (like Elijah’s was). I think this is, in part, what is meant by “the spirit and power of Elijah.”
But we know that Israel, as a whole, did not receive John’s message of repentance. So the Lord Jesus states concerning John, “Elijah truly shall first come, and restore all things. But I say unto you, That Elijah is come already, and THEY KNEW HIM NOT, BUT HAVE DONE UNTO HIM WHATSOEVER THEY LISTED” (Matthew 17:11,12).This brings to mind one more point. Jesus said that when Elijah came, he would “restore all things.” Can we not expect this to still happen? I believe we can. In Revelation 11:1-12 we see two men witnessing for God during the Great Tribulation and the manner in which they testify is similar to that of Elijah and Moses (see verses 5, 6). Whether or not they are the literal Elijah and Moses, or two men coming in the spirit and power of these two, remains to be seen. But their testimony may bring about the fulfillment of the Lord’s words, as well as the words of the prophet Malachi in Malachi 4:6.