Do the two witnesses minister in the first or last half of the tribulation?
The two witnesses minister during the first half of the tribulation, specifically the first three and one-half years. Their 1,260-day ministry ends at the middle of the tribulation, not at its conclusion, because their ascension and the earthquake occur at the midpoint, leaving the last half still future.
Les explains that the two witnesses are given power to prophesy for 1,260 days, which equals three and one-half years. He notes that prophesy can mean either telling the future or speaking forth the Word, and here they will speak forth God's Word as His witnesses. They will come to the nation of Israel and minister primarily in the area of Jerusalem. Their ministry ends when they hear a great voice from heaven saying, "Come up hither," and they ascend; in the same hour there is a great earthquake, and the tenth part of the city falls. Les emphasizes that this is not the end of the tribulation but the middle, so these two witnesses minister during the first three and one-half years.
And they heard a great voice from heaven saying unto them, Come up hither. And they ascended up to heaven in a cloud; and their enemies beheld them.
And the same hour was there a great earthquake, and the tenth part of the city fell, and in the earthquake were slain of men seven thousand: and the remnant were affrighted, and gave glory to the God of heaven.
More Questions
Do the events at the end of the two witnesses' ministry happen at the end of the tribulation?
The events at the end of the two witnesses' ministry—their ascension in verse 12 and the earthquake in verse 13—happen at the middle of the tribulation, not at the end.