It's also possible that the two witnesses are symbolically modeled after Moses and Elijah. Elijah's deed was proverbial among Jews in the first century. It seems clear, then, that the two witnesses are portrayed as coming in the power of both Moses and Elijah, two of the greatest prophets of the Jewish nation. The writer appears to be creating a symbolic universe for his readers in which he is making a connection between God's acts in Jewish history and through the church. Perhaps there is a literal aspect to the fire from heaven or other elements, but we cannot neglect their metaphorical meaning.
Fire coming from the mouth is a symbol used for powerful preaching.
However, Jeremiah did not do any miraculous works. He was a prophet who spoke God's word. We must be careful, then, how we interpret the images of Revelation. In any case, the imagery of Revelation 11 is so carefully worked out to coincide with the most noteworthy accomplishments of Elijah and Moses that it cannot be accidental. John is giving his hearer-readers a message.