Malachi 4:5

See, I am sending you Elijah the prophet before the day of the Lord comes, that great day, greatly to be feared.

Luke 1:17

And he will go before his face in the spirit and power of Elijah, turning the hearts of fathers to their children, and wrongdoers to the way of righteousness; to make ready a people whose hearts have been turned to the Lord.

Joel 2:31

The sun will be made dark and the moon turned to blood, before the great day of the Lord comes, a day to be feared.

Malachi 3:1

See, I am sending my servant, and he will make ready the way before me; and the Lord, whom you are looking for, will suddenly come to his Temple; and the angel of the agreement, in whom you have delight, see, he is coming, says the Lord of armies.

Isaiah 40:3

A voice of one crying, Make ready in the waste land the way of the Lord, make level in the lowland a highway for our God.

Malachi 4:1

For see, the day is coming, it is burning like an oven; all the men of pride and all who do evil will be dry stems of grass: and in the day which is coming they will be burned up, says the Lord of armies, till they have not a root or a branch.

Matthew 17:10-13

And his disciples, questioning him, said, Why then do the scribes say that Elijah has to come first?

Mark 9:11-13

And they put a question to him, saying, Why do the scribes say that Elijah has to come first?

John 1:21

And they said to him, What then? Are you Elijah? And he said, I am not. Are you the prophet? And his answer was, I am not.

Revelation 6:17

For the great day of their wrath is come, and who may keep his place?

Matthew 11:13-14

For all the prophets and the law were in force till John.

Matthew 27:47-49

And some of those who were near by, hearing it, said, This man is crying to Elijah.

Luke 7:26-28

But what did you go out to see? a prophet? Yes, I say to you, and more than a prophet.

Luke 9:30

And two men, Moses and Elijah, were talking with him;

John 1:25

And they put this question to him, saying, Why then are you giving baptism if you are not the Christ, or Elijah, or the prophet?

Acts 2:19-20

And wonders will be seen in heaven, and signs on the earth, blood and fire and smoke:

Treasury of Scripture Knowledge

Summary

Behold, I will send you Elijah the prophet before the coming of the great and dreadful day of the LORD:

Bible References

I will

Malachi 3:1
See, I am sending my servant, and he will make ready the way before me; and the Lord, whom you are looking for, will suddenly come to his Temple; and the angel of the agreement, in whom you have delight, see, he is coming, says the Lord of armies.
Isaiah 40:3
A voice of one crying, Make ready in the waste land the way of the Lord, make level in the lowland a highway for our God.
Matthew 11:13
For all the prophets and the law were in force till John.
Matthew 17:10
And his disciples, questioning him, said, Why then do the scribes say that Elijah has to come first?
Matthew 27:47
And some of those who were near by, hearing it, said, This man is crying to Elijah.
Mark 9:11
And they put a question to him, saying, Why do the scribes say that Elijah has to come first?
Luke 1:17
And he will go before his face in the spirit and power of Elijah, turning the hearts of fathers to their children, and wrongdoers to the way of righteousness; to make ready a people whose hearts have been turned to the Lord.
Luke 7:26
But what did you go out to see? a prophet? Yes, I say to you, and more than a prophet.
Luke 9:30
And two men, Moses and Elijah, were talking with him;
John 1:21
And they said to him, What then? Are you Elijah? And he said, I am not. Are you the prophet? And his answer was, I am not.

General references

Zechariah 14:1
See, a day of the Lord is coming when they will make division of your goods taken by force before your eyes.
Matthew 11:10
This is he of whom it has been said, See, I send my servant before your face, who will make ready your way before you.
Mark 9:11
And they put a question to him, saying, Why do the scribes say that Elijah has to come first?
Acts 2:19
And wonders will be seen in heaven, and signs on the earth, blood and fire and smoke:

Basic English, produced by Mr C. K. Ogden of the Orthological Institute - public domain