Revelation 11 3 And I will give power unto my two witnesses, and they shall prophesy a thousand two hundred and threescore days, clothed in sackcloth. 4 These are the two olive trees, and the two candlesticks standing before the God of the earth. 5 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. 6 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. 7 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. 8 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. 9 And they of the people and kindreds and tongues and nations shall see their dead bodies three days and an half, and shall not suffer their dead bodies to be put in graves. 10 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. 11 And after three days and an 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. 12 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.
These two Prophets are clearly mentioned in the Bible. They are clearly identified. And they were clearly foretold of their future task.
Daniel 12 8 And I heard, but I understood not: then said I, O my Lord, what shall be the end of these things? 9 And he said, Go thy way, Daniel: for the words are closed up and sealed till the time of the end. 10 Many shall be purified, and made white, and tried; but the wicked shall do wickedly: and none of the wicked shall understand; but the wise shall understand. 11 And from the time that the daily sacrifice shall be taken away, and the abomination that maketh desolate set up, there shall be a thousand two hundred and ninety days. 12 Blessed is he that waiteth, and cometh to the thousand three hundred and five and thirty days. 13 But go thou thy way till the end be: for thou shalt rest, and stand in thy lot at the end of the days.
Here is one of the two Witnesses of End Times identified. Daniel, prophet of the Old Testament will rise from his grave, to accomplish his task.
The other Witness, the one who was chosen to write the book of Revelations, was also told that he will prophecy in front of many people, nations, kings, of different tongues.
1 The Revelation of Jesus Christ, which God gave unto him, to shew unto his servants things which must shortly come to pass; and he sent and signified it by his angel unto his servant John: 2 Who bare record of the word of God, and of the testimony of Jesus Christ, and of all things that he saw.
Revelation 10 tells him and us, when and what he will have to do.
Revelation 10 And I saw another mighty angel come down from heaven, clothed with a cloud: and a rainbow was upon his head, and his face was as it were the sun, and his feet as pillars of fire: 2 And he had in his hand a little book open: and he set his right foot upon the sea, and his left foot on the earth, 3 And cried with a loud voice, as when a lion roareth: and when he had cried, seven thunders uttered their voices. 4 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 those things which the seven thunders uttered, and write them not. 5 And the angel which I saw stand upon the sea and upon the earth lifted up his hand to heaven, 6 And sware by him that liveth for ever 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: 7 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. 8 And the voice which I heard from heaven spake unto me again, and said, Go and take the little book which is open in the hand of the angel which standeth upon the sea and upon the earth. 9 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. 10 And I took the little book out of the angel's 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. 11 And he said unto me, Thou must prophesy again before many peoples, and nations, and tongues, and kings.