The following is an excerpt from The MacArthur New Testament Commentary on Revelation 11 .

And I will grant authority to my two witnesses, and they will prophesy for twelve hundred and sixty days, clothed in sackcloth. These are the two olive trees and the two lampstands that stand before the Lord of the earth. (Revelation 11:3-4)

The connection between this vision of the two preachers and the previous passage (vv. 1–2) should be clear. They are among God’s unique witnesses who will proclaim His message of judgment during the final stages of the Gentile trampling on Jerusalem—and will preach the gospel so that the Jewish remnant can believe and enjoy God’s protection.

Witnesses is the plural form of martus, from which the English word martyr derives, since so many witnesses of Jesus Christ in the early church paid with their lives. Since it is always used in the New Testament to refer to persons, the two witnesses must be actual people, not movements, as some commentators have held. There are two witnesses because the Bible requires the testimony of two people to confirm a fact or verify truth (Deut. 17:6; 19:15; Matt. 18:16; John 8:17; 2 Cor. 13:1; 1 Tim. 5:19; Heb. 10:28).

It will be their responsibility to prophesy. Prophecy in the New Testament does not necessarily refer to predicting the future. Its primary meaning is “to speak forth,” “to proclaim,” or “to preach.” The two witnesses will proclaim to the world that the disasters occurring during the last half of the Tribulation are the judgments of God. They will warn that God’s final outpouring of judgment and eternal hell will follow. At the same time, they will preach the gospel, calling people to repentance and faith in the Lord Jesus Christ. The period of their ministry is twelve hundred and sixty days, the last three and one-half years of the Tribulation, when Antichrist’s forces oppress the city of Jerusalem (v. 2), and many Jews are sheltered in the wilderness (12:6). The fact that they are actual preachers and not symbols of institutions or movements is indicated by the description of their clothing and behavior which follows.

clothed in sackcloth.?” (11:3b)

Sackcloth was rough, heavy, coarse cloth worn in ancient times as a symbol of mourning, distress, grief, and humility. Jacob put on sackcloth when he thought Joseph had been killed (Gen. 37:34). David ordered the people to wear sackcloth after the murder of Abner (2 Sam. 3:31) and wore it himself during the plague God sent in response to his sin of numbering the people (1 Chron. 21:16). King Jehoram wore sackcloth during the siege of Samaria (2 Kings 6:30), as did King Hezekiah when Jerusalem was attacked (2 Kings 19:1). Job (Job 16:15), Isaiah (Isa. 20:2), and Daniel (Dan. 9:3) also wore sackcloth.

The two witnesses will put on sackcloth as an object lesson to express their great sorrow for the wretched and unbelieving world, racked by God’s judgments, overrun by demon hordes, and populated by wicked, sinful people who refuse to repent. They will also mourn because of the desecration of the temple, the oppression of Jerusalem, and the ascendancy of Antichrist.

These are the two olive trees and the two lampstands that stand before the Lord of the earth. (11:4)

The question of who the two witnesses will be has intrigued Bible scholars over the years, and numerous possibilities have been suggested. John identifies them merely as the two olive trees and the two lampstands that stand before the Lord of the earth. That enigmatic description is drawn from Zechariah 4:1–14.

Zechariah’s prophecy looks forward to the restoration of Israel in the Millennium (cf. Zech. 3:8–10). The olive trees and lampstands symbolize the light of revival, since olive oil was commonly used in lamps. The connecting of the lamps to the trees is intended to depict a constant, spontaneous, automatic supply of oil flowing from the olive trees into the lamps. That symbolizes the truth that God will not bring salvation blessing from human power, but by the power of the Holy Spirit (cf. Zech. 4:6). Like Joshua and Zerubbabel, the two witnesses will lead a spiritual revival of Israel culminating in the building of a temple. Their preaching will be instrumental in Israel’s national conversion (Rev. 11:13; cf. Rom. 11:4–5, 26), and the temple associated with that conversion will be the millennial temple.

While it is impossible to be dogmatic about the specific identity of these two preachers, there are a number of reasons that suggest that they may be Moses and Elijah.

First, the miracles they will perform (destroying their enemies with fire, withholding rain, turning water into blood, and striking the earth with plagues) are similar to the judgments inflicted in the Old Testament by Moses and Elijah for the purpose of stimulating repentance. Elijah called down fire from heaven (2 Kings 1:10, 12) and pronounced a three-and-one-half-year drought on the land (1 Kings 17:1; James 5:17)—the same length as the drought brought by the two witnesses (Rev. 11:6). Moses turned the waters of the Nile into blood (Ex. 7:17–21) and announced the other plagues on Egypt recorded in Exodus chapters 7–12.

Second, both the Old Testament and Jewish tradition expected Moses and Elijah to return in the future. Malachi 4:5 predicted the return of Elijah, and the Jews believed that God’s promise to raise up a prophet like Moses (Deut. 18:15, 18) necessitated his return (cf. John 1:21; 6:14; 7:40). Jesus’ statement in Matthew 11:14 that “if you are willing to accept it, John [the Baptist] himself is Elijah who was to come” does not necessarily preclude Elijah’s future return. Since the Jews did not accept Jesus, John did not fulfill that prophecy. He came “in the spirit and power of Elijah, to turn the hearts of the fathers back to the children, and the disobedient to the attitude of the righteous, so as to make ready a people prepared for the Lord” (Luke 1:17).

Third, both Moses and Elijah (perhaps representing the Law and the Prophets) appeared with Christ at the Transfiguration, the preview of the Second Coming (Matt. 17:3?).

Fourth, both left the earth in unusual ways. Elijah never died, but was transported to heaven in a fiery chariot (2 Kings 2:11–12), and God supernaturally buried Moses’ body in a secret location (Deut. 34:5–6; Jude 9). The statement of Hebrews 9:27 that “it is appointed for men to die once and after this comes judgment” does not rule out Moses’ return, since there are other rare exceptions to that general statement (such as Lazarus; John 11:14, 38–44).

Since the text does not specifically identify these two preachers, the view defended above, like all other views regarding their identity, must remain speculation.