Seven Bowls 9.1: Moses & Elijah Alive?

Who are the 2 olive trees?
Can you think of someone in the bible that shut up the sky so it did not rain for three and a half years? 
Try 1 Kings 17:1, Luke 4:25 and James 5:17!

It was Elijah, the prophet, who was announcing God's judgment on King Ahab of Israel (perhaps better remembered for his wife, Jezebel). He also brought down fire from heaven to ignite a sacrifice, after he had challenged Baal’s prophets to do likewise.(1 Kings 18;36-38) 
Elijah seems to be used in the bible as a representative of all the 

But there is more to it than just collective representative status. 

The last of the Old Testament prophets, Malachi, said of him
I will send you the prophet Elijah before that great and dreadful day of the LORD comes.

That passage prompted people to ask Jesus if he claimed to be Elijah (e.g. Matthew 16:14). In fact Jesus seemed to indicate that Elijah was re-incarnated as John the Baptist (Matthew 11:14, 17:10-12). Elijah actually visited Jesus and talked with him and another re-incarnated person (Matthew 17:3)

So one of the olive trees is a representative of the prophets
Who had the power to turn water into blood? 
Try Exodus 7:17!

It was Moses - the giver of the law.
In Deuteronomy 18:14, Moses promised the people of Israel that God would send them another prophet like him, after he had departed. The idea that Jesus was a re-incarnated Moses seemed to occur to at least one of his disciples. (John 1:43-45)
The next day Jesus decided to leave for Galilee. Finding Philip, he said to him, "Follow me."
Philip, like Andrew and Peter, was from the town of Bethsaida. Philip found Nathanael and told him, "We have found the one Moses wrote about in the Law, and about whom the prophets also wrote—Jesus of Nazareth, the son of Joseph."
So it seems reasonable to assume that the other olive tree is Moses, the giver of the Law

Just think of one of the olive trees that fuel the lamp as Moses, who gave God’s Law to the people of Israel. 

Then think of the other olive tree as Elijah, the prophet who seems to be the archetype for all the later prophets who explained to the people the spirit in which they should interpret the Law of Moses. 
Olive Tree #1 = Moses Law
Olive Tree #2 = the Prophets interpretation of that Law

Did you notice the bit about fire coming from their mouths? 

A similar metaphor is applied to the Messiah in Revelation 19:11-21, only this time it is a sword. The implication seems to be that their words contain great power.
And what is the angel's explanation to Zechariah of the meaning of the lamp? 
It is the word of God. 

The words that Moses and the prophets spoke. They are the two anointed who stand by the Lord of the whole earth. (Zechariah 4: 14) 
So what's this got to do with the Book of Revelation?
In the context of Zechariah, we could probably think of the olive trees as Zerubbabel (the Persian appointed governor of Jerusalem) and Jeshua (the Jewish priest). 

In the context of this particular vision we could say it is Zerubbabel, as a type (or metaphor) for Jesus. 

Just as Zerubbabel was largely responsible for rebuilding the temple for the exiles, so will Jesus, the Messiah, be responsible for rebuilding the temple after the great tribulation (to quote Zechariah 4:6-7, 9)
Not by might, nor by power, but by my Spirit, says the LORD of hosts. 
What are you, O great mountain? Before Zerub'babel you shall become a plain; and he shall bring forward the top stone amid shouts of 'Grace, grace to it!'" 
"The hands of Zerub'babel have laid the foundation of this house; his hands shall also complete it. Then you will know that the LORD of hosts has sent me to you. 

One of these witnesses he’s Elijah
He shut the heavens stopped the rain
He raised the widow’s son in Sidon
Up from Sheol’s bed of pain
Old Elijah talking to the king
Bring out Baal’s prophets for a final fling
Get ‘em up on Carmel make them jump and shout
Rain fire from heaven in a final route

 One of those witnesses is Moses
The one who crossed the Red Sea
He put the hard word on old Pharaoh
Let the people go free

Moses (Law) & Elijah (Prophets) = 2 Witnesses