The apostle John tells us that, in a vision, "I saw another angel flying in the midst of heaven, having the everlasting gospel to preach to those who dwell on the earth; to every nation, tribe, tongue, and people . . ." Notice the essence of that everlasting gospel: "Fear God and give glory to Him . . . and worship Him who made heaven and earth, the sea and springs of water" (Revelation 14:6-7).
God's message to mankind is eternal and consistent. He has always emphasized the importance of our having a relationship with Him as our Creator. He said to Abraham, "And I will establish My covenant between Me and you and your descendants after you in their generations, for an everlasting covenant, to be God to you and your descendants after you" (Genesis 17:7). God later repeated similar words to the nation of Israel (Deuteronomy 29:13).
The term Kingdom of God implies much more than Jesus Christ's administration of the righteous laws of God over the earth. It also encompasses the very children of God—God's family. He reveals that the members of that family, which He is in the process of building, are His own sons and daughters who will share with Christ the administration of the laws of God over the nations.
Jesus promised, "To him who overcomes I will grant to sit with Me on My throne, as I also overcame and sat down with My Father on His throne" (Revelation 3:21). What will they then do? "And he who overcomes, and keeps My works until the end, to him I will give power over the nations" (Revelation 2:26).
A remarkable relationship exists between Jesus Christ and those who will share responsibilities with Him in the Kingdom of God. "In bringing many sons to glory, it was fitting that God, for whom and through whom everything exists, should make the author of their salvation perfect through suffering. Both the one who makes men holy and those who are made holy are of the same family. So Jesus is not ashamed to call them brothers" (Hebrews 2:10-11, NIV).
Not only are they the brothers and sisters of Jesus Christ, but God the Father regards them as His own sons and daughters. "As God has said: 'I will dwell in them and walk among them. I will be their God, and they shall be My people . . . I will be a Father to you, and you shall be My sons and daughters, says the LORD Almighty'" (2 Corinthians 6:16-18).
Jesus compared the Kingdom of God to "a mustard seed . . . which indeed is the least of all the seeds; but when it is grown it is greater than the herbs and becomes a tree, so that the birds of the air come and nest in its branches" (Matthew 13:31-32).
The gospel is the story of God building His family by first calling out of the world a small number of people who, like a mustard seed, will increase in number and scope until the earth is filled with the children of God.
No wonder Jesus said, "Let the little children come to Me, and do not forbid them; for of such is the kingdom of God" (Mark 10:14). The Kingdom of God will consist of the children of God who receive the gift of eternal life as spirit beings at the return of Jesus Christ.
The apostle Paul describes how this will occur: "Now this I say, brethren, that flesh and blood cannot inherit the kingdom of God; nor does corruption inherit incorruption. Behold, I tell you a mystery: We shall not all sleep, but we shall all be changed—in a moment, in the twinkling of an eye, at the last trumpet. For the trumpet will sound, and the dead will be raised incorruptible, and we shall be changed. For this corruptible must put on incorruption, and this mortal must put on immortality" (1 Corinthians 15:50-53).
From the beginning, God has wanted to offer humanity the most priceless of gifts: the gift of eternal life as a member of His family in the Kingdom of God. Even as Adam and Eve were escorted out of the Garden of Eden because of their sins, God had already planned another opportunity for human beings to share in a loving, personal and eternal family relationship with Him.
Jesus Christ is even now preparing for the Kingdom and a future with us (John 14:1-3). God the Father offers us the opportunity to enter the Kingdom as His own immortal sons. As the apostle Paul said, "you know how we exhorted, and comforted, and charged every one of you, as a father does his own children, that you would walk worthy of God who calls you into His own kingdom and glory" (1 Thessalonians 2:11-12).