The answer to this question is found in Isaiah 65:18-20 which reads, “But be glad and rejoice forever in what I create; for behold, I create Jerusalem for rejoicing, and her people for gladness. I will also rejoice in Jerusalem, and be glad in My people; and there will no longer be heard in her the voice of weeping and the sound of crying. No longer will there be in it an infant who lives but a few days, or an old man who does not live out his days; for THE YOUTH WILL DIE AT THE AGE OF ONE HUNDRED and the one who does not reach the age of one hundred shall be thought accursed” (NASB).

What a day that will be when the Lord Jesus Christ establishes His 1,000 year kingdom with Jerusalem as the capital of the earth. His people will be made to rejoice in that day and their tears will be dried up! And even more importantly, the Lord will rejoice in His people, for their days of rebellion will be over. This dramatic change will be the result of their New Birth, as we see in Ezekiel 36:25-28, “Then I will sprinkle clean water upon you, and you shall be clean; I will cleanse you from all your filthiness and from all your idols. I will give you a new heart and put a new spirit in you; I will take the heart of stone out of your flesh and give you a heart of flesh. I will put My Spirit within you and cause you to walk in My statutes, and you will keep My judgments and do them. Then you shall dwell in the land that I gave to your father; you shall be My people, and I will be your God” (NKJV).

Yet there will still be DEATH, as we see in verse 20. This verse teaches us that during the Millennium men and women will be blessed with longevity of life. It may be that some will actually live to the very end of the 1,000 years. This much is clear; infant mortality and premature death will be absent and thus if one dies at the age of 100 they will be considered a child. The fact that there is still the possibility of death means there is still SIN in the Millennium earth (for “the wages of SIN is DEATH”). If one sins outwardly in rebellion against God, he may “not reach the age of one hundred.” He will be cut off quickly and be looked upon as cursed by God.

It is obvious that those who enter the Millennium are believers, for as we saw from Ezekiel 36 they will be given a “new heart,” a “new spirit,” and the Holy Spirit as well. But they will NOT receive their glorified bodies at that time and thus they are still MORTAL (i.e. subject to death). There will also be children born to them as we see in Psalm 22:31, “They will come and declare His righteousness to A PEOPLE WHO WILL BE BORN, that He has done this.” Believers will share the good news of Christ (that He has finished the work to save them from their sins) to those people who are born. Yet it is obvious that those who do rebel against God and are cut off early will have rejected the gospel of God’s grace. And at the end of the Millennium there will also be many who join Satan in his final rebellion against God and they will be destroyed by fire (see Revelation 20:7-9). These too had refused to believe on the Lord Jesus Christ as their Savior. (266.5) (DO)