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."
Cross References (ranked by relevance)
And the woman fled into the wilderness, where she hath a place prepared of God, that they should feed her there a thousand two hundred and threescore days.
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.
One witness shall not rise up against a man for any iniquity, or for any sin, in any sin that he sinneth: at the mouth of two witnesses, or at the mouth of three witnesses, shall the matter be established.
And there was given unto him a mouth speaking great things and blasphemies; and power was given unto him to continue forty and two months.
And in that day did the Lord GOD of hosts call to weeping, and to mourning, and to baldness, and to girding with sackcloth:
And Jacob rent his clothes, and put sackcloth upon his loins, and mourned for his son many days.
And he was seen many days of them which came up with him from Galilee to Jerusalem, who are his witnesses unto the people.
And ye are witnesses of these things.
But ye shall receive power, after that the Holy Ghost is come upon you: and ye shall be witnesses unto me both in Jerusalem, and in all Judaea, and in Samaria, and unto the uttermost part of the earth.
This Jesus hath God raised up, whereof we all are witnesses.
The elders of the daughter of Zion sit upon the ground, and keep silence: they have cast up dust upon their heads; they have girded themselves with sackcloth: the virgins of Jerusalem hang down their heads to the ground.
This is the third time I am coming to you. In the mouth of two or three witnesses shall every word be established.
And I heard the man clothed in linen, which was upon the waters of the river, when he held up his right hand and his left hand unto heaven, and sware by him that liveth for ever that it shall be for a time, times, and an half; and when he shall have accomplished to scatter the power of the holy people, all these things shall be finished.
But there remained two of the men in the camp, the name of the one was Eldad, and the name of the other Medad: and the spirit rested upon them; and they were of them that were written, but went not out unto the tabernacle: and they prophesied in the camp.
And ye also shall bear witness, because ye have been with me from the beginning.
I have sewed sackcloth upon my skin, and defiled my horn in the dust.
And David lifted up his eyes, and saw the angel of the LORD stand between the earth and the heaven, having a drawn sword in his hand stretched out over Jerusalem. Then David and the elders of Israel, who were clothed in sackcloth, fell upon their faces.
And killed the Prince of life, whom God hath raised from the dead; whereof we are witnesses.
And I fell at his feet to worship him. And he said unto me, See thou do it not: I am thy fellowservant, and of thy brethren that have the testimony of Jesus: worship God: for the testimony of Jesus is the spirit of prophecy.
And from Jesus Christ, who is the faithful witness, and the first begotten of the dead, and the prince of the kings of the earth. Unto him that loved us, and washed us from our sins in his own blood,