It is the Savior Himself who arrives to initiates his millennial reign. For the life of me, why would he not immediately, as first order of business, identify which church is truly His church and denounce all others as false – as he had once done before?
The prophets of God have identified the true church time and again. But the things of God are understood (and accepted) by the Spirit of God. The Lord told Joseph Smith on one occasion—
Behold, if they will not believe my words, they would not believe you, my servant Joseph, if it were possible that you should show them all these things which I have committed unto you (D&C 5:7).
Here are the words of the prophet Joseph Smith regarding conditions during the millennium—
“Christ and the resurrected Saints will reign over the earth during the thousand years. They will probably not dwell upon the earth, but will visit it when they please or when it is necessary to govern it. There will be wicked men on the earth during the thousand years. The heathen nations who will not come up to worship will be visited with the judgments of God and must eventually be destroyed from the earth.” (Joseph Smith, Jr. DHC 5:212
And from Brigham Young—
“In the Millennium men will have the privilege of being Presbyterians, Methodists, or Infidels, but they will not have the privilege of treating the name and character of Deity as they have done heretofore. No, but every knee shall bow and every tongue confess to the glory of God the Father that Jesus is the Christ” (Journal of Discourses 12:274).
And from the scriptures—
And again, verily, verily, I say unto you that when the thousand years are ended, and men again begin to deny their God, then will I spare the earth but for a little season (D&C 29:22).
So agency will continue to be in force, and the dispositions of men will not change all that much. The eye sees only what the mind gives it power to see, and the mind accepts only what the intelligence of the intellect gives it power to accept. When two different people see the Savior coming in the clouds of heaven in power and great glory, one will fall on his knees in worshipful adoration and the other will say, “What in the world is that??”