John the Baptist came in the spirit and power of Elijah. In other, he was a replica of Elijah. However the actual Elijah will indeed come to earth and preach to Israel before the Day of the LORD. See
Revelation 11. And the Lord Jesus will come to earth AFTER the Day of the LORD.
“However the actual Elijah will indeed come to earth to preach to Israel before the Day of the LORD.” Matthew 11:12-15 And from the days of John the Baptist until now the kingdom of heaven suffereth violence, and the violent take it by force. [13] For all the prophets and the law prophesied until John. [14] And
if ye will receive it , this is Elias, which was for to come. [15] He that hath ears to hear, let him hear.
Numerous times the Lord told them Elijah had already come. John the Baptist. 2 Kings 2:9 And it came to pass, when they were gone over, that Elijah said unto Elisha, Ask what I shall do for thee, before I be taken away from thee. And Elisha said, I pray thee, let a double portion of thy spirit be upon me.
Jesus as Elisha receives a “double portion” of the Holy Spirit: A double portion of that of John the Baptist’s. (Luke 1:15)(Luke 1:41). As Elisha received a double portion of Elijah's: Jesus received doubled John the Baptist’s portion.
1 Kings 19:19
[19] So he departed thence, and found Elisha the son of Shaphat, who was plowing with twelve yoke of oxen before him, and
he with the twelfth: and Elijah passed by him, and
cast his mantle upon him.
As John the Baptist lifted off his mantle (yoke)and placed it on Jesus.
1 Kings 19:20-21
[20] And he left the oxen, and ran after Elijah, and said, Let me, I pray thee, kiss my father and my mother, and then I will follow thee. And he said unto him, Go back again: for what have I done to thee? [21] And he returned back from him, and took a yoke of oxen, and slew them, and boiled their flesh with the instruments of the oxen, and gave unto the people, and they did eat. Then he arose, and went after Elijah, and ministered unto him.
2 Kings 6:21-23
[21] And the king of Israel said unto Elisha, when he saw them, My father,
shall I smite them ?
shall I smite them ? [22] And he answered,
Thou shalt not smite them :
wouldest thou smite those whom thou hast taken captive with thy sword and with thy bow? set bread and
water before them,
that they may eat and drink, and go to their master. [23] And he prepared great provision for them: and when they had eaten and drunk, he sent them away, and they went to their master. So the bands of Syria came no more into the land of Israel.
Romans 12:20-21
[20] Therefore if thine enemy hunger, feed him; if he thirst, give him drink: for in so doing thou shalt heap coals of fire on his head. [21] Be not overcome of evil, but overcome evil with good.
Luke 9:54-56
[54] And when his disciples James and John saw this , they said, Lord, wilt thou that we command fire to come down from heaven, and
consume them, even as Elias (Elijah) did? [55] But he turned, and
rebuked them, and said, Ye know not what manner of spirit ye are of. [56] For the Son of man is not come to destroy men's lives, but to save them .