In your answer to the question “Sin In The Millennium?” you said “Lately I’ve had the suspicion that a third testament may emerge for the Millennial Age, just like a second one emerged for the Church Age. There are simply too many unanswered questions.” In light of Rev. 22:18 (“If any man shall add unto these things, God shall add unto him the plagues”, etc.) would it not be correct to believe that the Holy Scripture is pretty much complete in its fullness? And since we will have the King Jesus reign with humankind on Earth during the Millennium, will the Lord’s physical presence not be enough to provide all the answers to people’s questions?
I was merely voicing an opinion based on how the New Testament came to be. But the warning in Rev. 22:18 is against adding anything to the Book of Revelation, and is addressed to “any man” so it would not apply to God having a 3rd Testament published. And remember, most of the Old Testament was written while God dwelt in the presence of the Israelites.
Even with the New Covenant in place, life on Earth during the Millennium will be far different from it has been like during the Church Age. There isn’t a single word in the Bible about how people on Earth will come to the Lord and be saved, what will be expected of them while they’re alive, or what will happen to them when they die. And there isn’t anything about the Age that will come after the 1000 years are over. We know what will happen to unbelievers, but not believers. The Lord’s method in Old and New Covenant times has been to provide both teachers and the written word. Based on that I suspect He’ll do the same for the Millennium.