It will be necessary now to say something respecting the references in the Apocalypse to the Old Testament prophecies.

     These are very numerous: I can only notice three. The first shall be Rev. xi. 3, 4, “An I will give power unto my two witnesses, and they shall prophesy a thousand two hundred and threescore days, clothed in sackcloth. These are the two olive trees, and the two candlesticks standing before the God of the earth.” Now the prophet Zechariah saw in a vision a candlestick with a bowl on the top of it, and his seven lamps thereon, and seven pipes to the seven lamps, and he saw also two olive trees by it, which apparently supplied the candlestick. There can be no doubt but that the Apocalyptic seer alludes to this vision of Zechariah, but he introduces many features not in Zechariah, particularly that the two witnesses shall prophesy a thousand two hundred and threescore days, clothed in sackcloth; that if any man will hurt them, fire proceedeth out their mouth, and devoureth their enemies; and they have power to shut heaven, and to turn waters into blood. Now it is to be noticed that the explanation given by Zechariah is only for the encouragement of Zerubbabel, but the power given to St. John’s two witnesses and olive trees is for much more; it is for vengeance upon their enemies—or rather upon God’s enemies—to smite them with the plagues of Egypt, and at the end of their testimony the beast, i.e., according to the most approved expositors, the “world-power,” shall destroy them. So there is a reference to the prophecy of Zechariah and very much more.

     This prophecy of Zechariah then seems to have had a very limited fulfilment, and that it waits for a far completer fulfulment in the latter days.

(M. F. Sadler, The Revelation of St. John the Divine: With Notes Critical and Practical, London: George Bell and Sons, 1899; From Introduction, xxv)