As I have been working my way through the period of Israel 's history in the land and then into the exile, I have been doing so with Genesis 1:26-28 in mind, where God gave man dominion over the earth. Genesis 3, of course, documents man's fall and subsequent loss of that ability to exercise dominion, but the purpose of God still stands.
As I read through the history of God's chosen nation and the human kings who were to act as mediators of God's royal authority on the earth, I am struck by their role and their failure in two respects. First, although annointed by God, even David could not fulfill the assignment given in Genesis 1 because of the curse of sin. Second, since that assignment has never been fulfilled, it follows that one day it must be fulfilled because God's words will not return to him void and unfulfilled.
That fulfillment will occur during the Millennial Kingdom when Jesus Christ, the perfect Man, reigns over the earth, and we with Him. So it occurs to me, just how important is it that Jesus Christ reign on the earth? It is critical, because His reign, among other things, fulfills a purpose of God for man that, to this day, stands unfulfilled. Far from being an unimportant doctrine, the millennial reign of Jesus Christ is vitally important because it restores man to His earthly purpose, fulfills the "marching" orders God destined man for when He created us, and vindicates God against any charge that His purposes went unfulfilled.
That's pretty cool!