How does the world react to the testimony of the two witnesses?
After demonstrating God's power to the people in Jerusalem and the world, "...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" (Revelation 11:7), a global Christmas party will begin: "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" (verse 10).
How will the two witnesses torment the people on earth? By proclaiming the truth. But as we already mentioned, they are the reason it doesn't rain and the water turns into blood. Plus, they will have power over plagues upon the earth to punish mankind.
Their bodies will lie in the streets of Jerusalem, but they will arise from death after three days, and will be seen by the people in Jerusalem. Then they will hear the voice of God say: "...come up hither." As a result, we read in verse 13: "...and the remnant were affraighted, and gave glory to the God of heaven." The resurrection and ascension of the two witnesses is the turning point for the Jewish people during the Great Tribulation.