The Two Witnesses will have to do their preaching in the presence of the Satan's opposition, who has become Antichrist in the flesh.
Zechariah asked the angel talking with him, "What are these 'Two Olive Trees' on the right side of the candlestick and on the left side?"

           And the angel said, "These are the 'Two Anointed Ones,' that stand by the Lord of the whole earth."
These Two Witnesses are called the Two Olive Trees and the Two Candlesticks that stand before the God of the earth.

           Zechariah the prophet saw in a vision a golden candlestick with a bowl upon the top of it and the seven lamps on it and seven pipes to the seven lamps; and two olive trees by it, one on the right side of the bowl and the other on the left side.
The Mighty Angel [Christ] called the Two Witnesses, My Two Witnesses implying that witnessing was their mission.

         When they witnessed on the Mt of Transfiguration and Two Men witnessed at the Tomb that Jesus had risen and it was Two Men who stood by and witnessed to the Disciples as Jesus ascended into Heaven.  In all three incidents the Men were clothed in shining garments.

                It seems that Moses was resurrected and Elijah translated for the purpose of Witnessing.
Seeing what happens during the period the Two Witnesses testify, which will be the last half of the Week, or 3 1/2 years, they can't be any other than Moses and Elijah.

           Elijah will more than likely shut up the Heavens that it will no longer rain, and there is to be a Fire Test such as he did on Mt. Carmel in the days of King Ahab.

                    As the Plagues that were poured out on the Egyptians will be similar to those pour out in Revelation, by who other than Moses.
The Bible says these Two Witnesses will have power to shut Heaven that it rain not in the days of their prophecy.

        And they have power over waters to turn them to blood and to smite the earth with all plagues, as often as they will.
It's believed that one of the Two Witnesses will be Elijah. But who will be the other one?

        Many think Moses will be the second one, others say he will be Enoch.  They claim both Enoch and Elijah were caught up in their bodies without dying, so that they might come back again in their bodies and die.  This leaves out Moses because he was said to have died and cannot die again.
The Two Witnesses are men. They are not churches or systems or bodies of witnesses.

        They prophesy and are clothed in sackcloth; which can't be said of other than persons and there are two of them.

                They have the power to shut heaven that it doesn't rain in the days of their prophecy.
After the Mighty Angel had given John instructions on measuring the Temple, He said 'And will give power unto My Two Witnesses, and they shall prophecy a thousand two hundred and threescore days.'

         That is equal to 42 months of 30 days each, or 3 1/2 years, then is the time when the two witnesses are to prophesy which is the last half of the Week, or 7 years, the time of the Great Tribulation.
John was told to measure only the main Temple and to leave out the Court that surrounded it.
      
        Solomon's Temple had two courts, the Court of the Priests and the Court of the Gentiles.

                The Court of this new Temple, as well as the Holy City (Jerusalem), is to be trodden under foot of the Gentiles for 42 months (3 1/2) years, this period must refer to the last half of the Seventieth Week, after the Antichrist breaks his Covenant with the Jews and desecrates the Temple, for Jerusalem must be trodden down of the Gentiles until the Times of the Gentiles is fulfilled and that will not end until the Battle of Armageddon.
The Temple that the Jews will build on their return to Jerusalem will probably be destroyed by the Earthquake that destroys the tenth part of the City, because that Earthquake will happen with the Earthquake that will occur at the breaking of the Seventh Seal, the sounding of the Seven Trumpet and the pouring out of the Seventh Vial.
The Antichrist will cause the Abomination of Desolation spoken of by Daniel the Prophet, probably the Image of the Beast, to be set up in the Holy Place.

          This isn't to be the Millennial Temple described by Ezekiel because that one will be built at Shiloh, in the middle of the Holy Oblation and not until after the physical changes that will take place at the return of Christ shall have changed the surface of the Land of Palestine.
The angel that told John to rise and measure the Temple was the same Mighty Angel that handed him the Little Book to eat.

         And as they were both still on the earth, the Temple that John was told to measure was the Temple at Jerusalem.

                   This has to be the future temple that is to be built at Jerusalem. It is clear that there will be a Temple at Jerusalem during the Antichrist's rule because he will sit in it and proclaim himself God.
The Two Witnesses
Revelation 11:1-14

"And there was given me a reed like unto a rod: and the angel stood, saying, Rise and measure the Temple of God, and the Altar, and them that worship therein. But the Court which is without the Temple leave out; and measure it not; for it is given unto the Gentiles: and the Holy City shall they tread under foot Forty and Two Months.
And I will give power unto My Two Witnesses, and they shall prophesy a Thousand Two Hundred and Three-score Days, clothed in sackcloth. These are the Two Olive Trees and the Two Candlesticks standing before the God of the earth.
And if any man will hurt them, fire proceedeth out of their mouth and devoureth their enemies: and if any man will hurt them, he must in this manner be killed. These have power to shut heaven that it rain not in the days of their prophecy: and have power over waters to turn them to blood and to smite the earth with all plagues, as often as they will.
And when they shall have finished their testimony, the beast that ascendeth out of the bottomless pit shall make war against them, and shall overcome them and kill them.
And their dead bodies shall lie in the street of the Great City, which spiritually is called Sodom and Egypt, where also our Lord was crucified.
And they of the people and kindreds and tongues and nations shall see their dead bodies three Days and a half, and shall not suffer their dead bodies to be put in graves.
And they that dwell upon the earth shall rejoice over them, and make merry, and shall send gifts one to another; because these two prophets tormented them that dwelt on the earth.
And after three days and a half the Spirit of Life from God entered into them, and they stood upon their feet; and great fear fell upon them which saw them.
And they heard a great voice from Heaven saying unto them, Come Up Hither and they ascended up to Heaven in a cloud; and their enemies beheld them.
And the same hour was there a great earthquake and the tenth part of the City fell, and in the earthquake were slain of men seven thousand: and the remnant were affrighted, and gave glory to the God of Heaven."
God revealed to the Old Testament Prophets that in His timing He would make the Mystery clear and when the Seventh Trumpet sounds, the Mystery of God will be finished.

            Because then the Mystery of Iniquity would be revealed, in whom Satan will dwell after he is cast out of Heaven and in his destruction, and the binding of Satan, and the setting up of the Millennial Kingdom of Christ, shall the promises be fulfilled to the Prophets, that peace and righteousness will reign on the earth.
The Finished Mystery

The Seventh Trumpet sounds the Mystery of God.

        This isn't the Mystery of the Church, that was finished by taking the Church out in chapter four. That Mystery wasn't known to the Prophets.

                The Mystery of God is why God permitted Satan to cause the fall of man causing sin and misery and death into the world.
As John read the deliverances that were to come to his people and the final victory of the Lamb and the setting up of The Kingdom, the Little Book was as sweet as honey to his taste, but when he meditated on the awful sufferings that would come to the world and on the Jews under the rule of the Beast/Antichrist and during the pouring out of the Vials, it was bitter to his soul.
The Little Book, is probably the Book that Daniel was told to seal up.

        It contained things that were not to be revealed until the time of the end, not the end of time, but the end of the times of the Gentiles which takes place the last half of Daniel's seventieth week, with The Great Tribulation Period.

            If this is true, then the Little Book is a preview of the things that are to come upon Daniel's people in the last half of Daniel's seventieth week. The effect on John's reading of this Little Book seems to confirm it.
John was then told to, 'Go, take the Little Book' which is open in the hand of the angel which stands on the sea and on the earth.

         At this time, John is back on earth. And when he took the Little Book, the angel said to him, 'Take and eat it up; and it shall make thy belly bitter and it shall be in thy mouth sweet as honey'

                 When John had eaten the Book it was as the angel had said, sweet to his mouth and bitter to his stomach.
When the Mighty Angel cried with a loud voice, John heard seven thunders utter their voices.

         These Thunders spoke, because John heard what they said, and as he had been commanded to write what he saw and heard, he proceeded to write what the voices of the seven thunders said, but he was told to seal up those things which the seven thunders said and not write them.

                 What they said hasn't ever been revealed, but will be when the time comes to make the revelation.
This same Mighty Angel speaks of the Two Witnesses, as My Witnesses,  which is further evidence that this Mighty Angel has to be Jesus Christ Himself.

        This interpretation makes it clear that when this Angel places His right foot on the sea and His left foot on the earth and swears that there will be 'Time No Longer' or 'No Longer Delay', it is Jesus taking possession of the Earth and Sea and declaring that there will no longer be delay in taking it from Satan.
The Mighty Angel is clothed in a cloud, there is a rainbow on His head, His face is as it were the sun, and His feet as pillars of fire.

         No ordinary angel has ever before or since described in the Word of God as appearing like that.

                  Then He is said to be crying with a loud voice, as a lion roaring and Christ is spoken of in Revelation as the Lion of the Tribe of Judah.
Then the Mighty Angel's description seems to point to the same person that John saw standing in the middle of the Lampstands [Jesus Himself].
We do not know who this mighty angel is unless he is Christ Himself.

          In the Old Testament the Son of God was called the Angel of the Lord and because we are in that part of the Book of Revelation that deals mainly with Israel it is what we can expect to hear.
The Interval Between the Sixth
and Seventh Trumpets
The Little Book
Revelation10:1-11

"And I saw another mighty angel come down from Heaven, clothed with the cloud: and a Rainbow was upon His head, and His face was as it were the Sun, and His feet as Pillars of Fire: and He had in His hand a Little Book open: and He set His right foot on the Sea, and His left foot on the earth, and cried with a loud voice, as when a lion roareth: and when He had cried Seven Thunders uttered their voices.
And when the Seven Thunders had uttered their voices, I was about to write: and I heard a voice from Heaven saying unto me, Seal up thoses things which the Seven Thunders uttered, and write them not.
And the Angel which I saw stand upon the sea andupon the earth lifted up His hand to Heaven, and swear by Him that liveth forever and ever, who created heaven, and the things that therein are, and the earth, and the things that therein are, and the sea, and the things which are therein, that there should be time no longer: but in the days of the voice of the seventh angel, when he shall begin to sound, the mystery of God should be finished, as He hath declared to His servants the Prophets.
And the voice which I heard from Heaven spake unto me again, and said, God and take the Little Book which is open in the hand of the angel which standeth upon the sea and upon the earth.
And I went unto the angel, and said unto him, Give me the Little Book.
And he said unto me, take it, and eat it up: and it shall make thy belly bitter, but it shall be in thy mouth sweet as honey.
And I took the Little Book out of the angels' hand, and ate it up; and it was in my mouth sweet as honey; and as soon as I had eaten it, my belly was bitter.
And He said unto me, thous must prophesy again before many peoples, and nations, and tongues, and kings."