Nice Topic for discussion.
The Watchtower has the Church Age ending in 1914 ....that's their biggest problem in interpreting scripture.
The 144K are future yet-to-be-seen Israelis, just like it says.
“Then I heard the number of those who were sealed: 144,000 from all the tribes of Israel” (Revelation 7:4)
This fits the initial claim that the book of Revelation is about future events...prophecy. It would be illogical to assume this is a symbolic characterization of then-living Christians that extended until WT leaders effectively shut down the "Church Age" with their heretical 1914-gentile-times-has-ended teachings.
Rather:
1. The New Testament is still open for business (The WT claims the NT was written only for the 144K and that all positions are filled)
2. All Christian believers (Christ Alone as their Mediator) are anointed, this is clear in scripture
3. When the church age does near it's end, the rapture will take place and evacuate believers from earth in glorified bodies like Jesus had after his resurrection
4. After this (or around this time) the temple in Jerusalem will be rebuilt and animal sacrifices will continue there (as they already have in the past few years nearby)
5. 144,000 Israelis who "get it" will be preaching Jesus during the tribulation period leading up to Armageddon.
The tribulation period is a future seven-year period of time in which God will allow human leaders (the Anti-Christ and his minions) a much greater reign of terror than has ever been previously seen. Their reign of terror is in a sense God's judgment against those who reject Him and will complete His plan of salvation for the nation of Israel.
All of this is according to God’s revelation to the prophet Daniel (Daniel 9:24–27). The 144,000 Jews are a sort of “first fruits” (Revelation 14:4) of a redeemed Israel which has been previously prophesied (Zechariah 12:10; Romans 11:25–27), and their mission seems to be to evangelize the post-rapture world and proclaim the gospel during the tribulation period. As a result of their ministry, millions—“a great multitude that no one could count, from every nation, tribe, people and language” (Revelation 7:9)—will come to faith in Christ.
Jesus will literally rule for 1000 years on the throne of David his fore-father from the re-built 3rd temple in Jerusalem. The modern nation of Israel will one day welcome their long-ago crucified King.
1. Church-age believers will have glorified bodies. Although their citizenship is in heaven, they will doubtless be very active in governmental activities on and over earth. They will have physical bodies suitable for life in heaven and earth, like Jesus had. "We will be like him".
2. Redeemed Israel and the "great multitude" (many other nation groups who survive the tribulation period) will continue living on earth as subjects of the King.
This is the mainstream Christian view.