Purps,
The 1 Cor. "end" of Jesus' 1000 year reign isn't the same as Matt. "conclusion of the system of things".
Botchtower says there are two fulfillments for Matthew's "conclusion of the system of things." The first century end of the Mosaic/Jewish system was the destruction of Jerusalem by Rome in 70 CE. The "Primary Fulfillment" as far as the dubs are concerned is the conclusion of Satan's system of things at the Great Tribulation/Armageddon... coming very, very soon now.
A thousand years later, after Jesus has rebuilt the global pair-uh-dice, everybody is perfect, and little J gives it all back to big daddy J. THE END... well except...
*** re chap. 41 p. 300 par. 18 God’s Day of Judgment—Its Joyful Outcome! ***
Thus, the program that the apostle Paul describes in his letter to the Corinthians will come to completion: "For [Jesus] must rule as king until God has put all enemies under his feet. As the last enemy, [Adamic] death is to be brought to nothing." What happens next? "When all things will have been subjected to him, then the Son himself will also subject himself to the One who subjected all things to him." In other words, Jesus "hands over the kingdom to his God and Father." (1 Corinthians 15:24-28) Yes, Jesus, having conquered Adamic death through the merit of his ransom sacrifice, will hand over a perfected human family to his Father, Jehovah. It is evidently at this point, at the end of the thousand years, that Satan is released and the final test takes place to determine whose names will remain permanently recorded in the scroll of life. "Exert yourselves vigorously" so that your name may be among them!—Luke 13:24; Revelation 20:5.
So, there's "the conclusion", then a thousand years later "the end", which isn't really the end. It's the beginning of the end, since Satan is going to successfully distract BILLIONS to rebel and get slaughtered by big daddy J. Then it's the end of the end.
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