After the transfiguration Jesus’s disciples asked Him about the coming of Elijah.  This is recorded in both Matthew and Mark.  Jesus’s response in both passages is, “Elijah is coming first and will restore all things”.

Mat 17:10  And His disciples asked Him, saying, “Why then do the scribes say that Elijah must come first?“
Mat 17:11  Jesus answered and said to them, “Indeed, Elijah is coming first and will restore all things.
Mat 17:12  But I say to you that Elijah has come already, and they did not know him but did to him whatever they wished. Likewise the Son of Man is also about to suffer at their hands.”
Mat 17:13  Then the disciples understood that He spoke to them of John the Baptist.

Mar 9:11  And they asked Him, saying, “Why do the scribes say that Elijah must come first?“
Mar 9:12  Then He answered and told them, “Indeed, Elijah is coming first and restores all things. And how is it written concerning the Son of Man, that He must suffer many things and be treated with contempt?
Mar 9:13  But I say to you that Elijah has also come, and they did to him whatever they wished, as it is written of him.”

Elijah is coming first and will restore all things

There are two main ways of understanding the phrase, “Elijah is coming first and will restore all things”. 

One way of understanding the phrase is that it refers solely to John the Baptist.  This is perhaps indicated by Matthew 17:13, “the disciples understood that He spoke to them of John the Baptist”.  The restoration of “all things” must then be understood as “all manner of things” since John the Baptist arguably did not restore all things.  This is a legitimate interpretation of the text, but it is not a correct translation.  All published translations have “all things,” “everything,” or a close equivalent.  

The other way of understanding the phrase is that it refers to an end time Elijah to come who will “restore all things” before the second coming of Jesus Christ.  It is then understood that John the Baptist was an Elijah type figure from Matthew 17:12 when Jesus said of him “Elijah has already come”.

A timeline of Elijahs

We will now review all the Scriptures pertaining to the coming of Elijah to see if they support the notion of an end time Elijah or not.

Malachi prophesied of a messenger whom God would send to prepare the way of the coming of Jesus Christ.

Mal 3:1  “Behold, I send My messenger, And he will prepare the way before Me. And the Lord, whom you seek, Will suddenly come to His temple, Even the Messenger of the covenant, In whom you delight. Behold, He is coming,” Says the LORD of hosts.

The gospel writers quoted this when they explained that John the Baptist fulfilled this prophecy.

Mat 11:10  For this is he [John the Baptist] of whom it is written: ‘BEHOLD, I SEND MY MESSENGER BEFORE YOUR FACE, WHO WILL PREPARE YOUR WAY BEFORE YOU.’

Mar 1:2  As it is written in the Prophets: “BEHOLD, I SEND MY MESSENGER BEFORE YOUR FACE, WHO WILL PREPARE YOUR WAY BEFORE YOU.”
Mar 1:3  “THE VOICE OF ONE CRYING IN THE WILDERNESS: ‘PREPARE THE WAY OF THE LORD; MAKE HIS PATHS STRAIGHT.'”
Mar 1:4  John came baptizing in the wilderness and preaching a baptism of repentance for the remission of sins.

Luk 7:26  But what did you go out to see? A prophet? Yes, I say to you, and more than a prophet.
Luk 7:27  This is he [John the Baptist] of whom it is written: ‘BEHOLD, I SEND MY MESSENGER BEFORE YOUR FACE, WHO WILL PREPARE YOUR WAY BEFORE YOU.’

Malachi also prophesied that God would send an Elijah before “the great and dreadful day of the LORD”, which is a reference to the end time.

Mal 4:5  Behold, I will send you Elijah the prophet Before the coming of the great and dreadful day of the LORD.
Mal 4:6  And he will turn The hearts of the fathers to the children, And the hearts of the children to their fathers, Lest I come and strike the earth with a curse.

The angel who appeared to Zacharias, the father of John the Baptist, quoted Malachi 4:6.

Luk 1:16  And he [John the Baptist] will turn many of the children of Israel to the Lord their God.
Luk 1:17  He will also go before Him in the spirit and power of Elijah, ‘TO TURN THE HEARTS OF THE FATHERS TO THE CHILDREN,’ and the disobedient to the wisdom of the just, to make ready a people prepared for the Lord.”

Moving on, Isaiah prophesied of a messenger preparing the way of Jesus Christ coming.

Isa 40:3  The voice of one crying in the wilderness: “Prepare the way of the LORD; Make straight in the desert A highway for our God.
Isa 40:4  Every valley shall be exalted And every mountain and hill brought low; The crooked places shall be made straight And the rough places smooth;
Isa 40:5  The glory of the LORD shall be revealed, And all flesh shall see it together; For the mouth of the LORD has spoken.”

The gospel writers quoted this passage in Isaiah when they explained that John the Baptist fulfilled this prophecy.

Mat 3:1  In those days John the Baptist came preaching in the wilderness of Judea,
Mat 3:2  and saying, “Repent, for the kingdom of heaven is at hand!”
Mat 3:3  For this is he who was spoken of by the prophet Isaiah, saying: “THE VOICE OF ONE CRYING IN THE WILDERNESS: ‘PREPARE THE WAY OF THE LORD; MAKE HIS PATHS STRAIGHT.’ “

Luk 3:3  And he [John the Baptist] went into all the region around the Jordan, preaching a baptism of repentance for the remission of sins,
Luk 3:4  as it is written in the book of the words of Isaiah the prophet, saying: “THE VOICE OF ONE CRYING IN THE WILDERNESS: ‘PREPARE THE WAY OF THE LORD; MAKE HIS PATHS STRAIGHT.
Luk 3:5  EVERY VALLEY SHALL BE FILLED AND EVERY MOUNTAIN AND HILL BROUGHT LOW; THE CROOKED PLACES SHALL BE MADE STRAIGHT AND THE ROUGH WAYS SMOOTH;
Luk 3:6  AND ALL FLESH SHALL SEE THE SALVATION OF GOD.’ “

Joh 1:23  He [John the Baptist] said: “I am ‘THE VOICE OF ONE CRYING IN THE WILDERNESS: “MAKE STRAIGHT THE WAY OF THE LORD,” ‘ as the prophet Isaiah said.”

Zacharias, the father of John the Baptist, also prophesied that John the Baptist would prepare the way of Jesus Christ.

Luk 1:76  “And you [John the Baptist], child, will be called the prophet of the Highest; For you will go before the face of the Lord to prepare His ways,
Luk 1:77  To give knowledge of salvation to His people By the remission of their sins,

Clearly, John the Baptist fulfilled the prophecy about preparing the way of the Lord in Isaiah 40:3.  However, Isaiah 40:4-5, although quoted in Luke 3:5-6, was not fulfilled during the time of John the Baptist.  It is clearly a future event associated with the second coming of Jesus Christ.

Let’s summarise the evidence for an end time Elijah.

Firstly, there is the reference to the end time in Malachi 4:5.  If this refers only to John the Baptist then why the reference to the day of the LORD which is 2000 years later?

Mal 4:5  Behold, I will send you Elijah the prophet Before the coming of the great and dreadful day of the LORD.

Secondly, there is also Isaiah 40:4-5 which has not been fulfilled which is clearly associated with John the Baptist (who is a type of Elijah).

Isa 40:4  Every valley shall be exalted And every mountain and hill brought low; The crooked places shall be made straight And the rough places smooth;
Isa 40:5  The glory of the LORD shall be revealed, And all flesh shall see it together; For the mouth of the LORD has spoken.”

Conclusion

Is there an end time Elijah to come?  Based on Malachi 4:5 and Isaiah 40:4-5, it certainly looks like it.