Following the creation of Adam and Eve in the Garden of Eden at the end of the sixth creative day, everything was perfect; no flaw at all, for Genesis 1:31 says: "After that God saw everything he had made and look ! it was very good. And there came to be evening and there came to be morning, a sixth day." However, rebellion broke out, with Eve giving ear to the "original serpent", Satan the Devil and then Adam listening to his wife's voice by eating from the "tree of knowledge of good and bad".(Gen 3:6,7; Rev 12:9)
Now, there was a flaw in God's creative handiwork, a flaw that has wreaked havoc upon all of mankind, bringing death.(Rom 5:12; Isa 25:7,8) How did God respond ? He purposed to make a provision for the forgiveness of sins through Christ Jesus.(Rom 5:8) God also established a governmental arrangement to manage the crisis. This arrangement is called "the kingdom of God". It is set up as a subsidiary of God's universal rulership and has a specific purpose.(Dan 2:44,45)
Jesus taught his followers: "You must pray, then, this way: 'Our Father in the heavens, let your name be sanctified. Let your kingdom come. Let your will take place, as in heaven, also upon the earth.' "(Matt 6:9,10) This prayer, known to many as the Our Father, or the Lord's Prayer, explains the purpose of God's kingdom. By means of God's kingdom, God's name, which is Jehovah, will be hallowed or sanctified - cleansed of all reproach that has been heaped upon it.(Ps 83:18)
Also, in order for God's "will (to) take place, as in heaven, also upon the earth", what is it that God's kingdom must restore ? The relationship between God and humans that Adam lost as a "son of God".(Luke 3:38) The kingdom will also serve to establish a paradise on the earth in which "meek" ones, subjects of God's kingdom, can enjoy an "abundance of peace".(Ps 37:11, 29; Matt 5:5) Thus, God's kingdom will undo all the damage done by the original sin of Adam and will make God's loving purpose for the earth a reality.(Rev 21:3,4) This kingdom and what it will accomplish is, in fact, the main message of the Bible. But what is God's kingdom ?
At Isaiah 9:6, it says of Jesus, that "the government shall be upon his shoulder".(King James Bible) God's kingdom is a real government that has great power, with Jesus as it's king. At Daniel 2:44, we are given a glimpse of it's power: "The God of heaven will set up a kingdom that.....will crush and put an end to all [human] kingdoms." Hence, it will permanently remove all human governments from the earth. Moreover, in contrast to human governments that come and go over the course of human history, God's kingdom "will never be brought to ruin."
In a "dream and visions" given to Daniel, he beholds "someone like a son of man" who gains access to the "Ancient of Days", God. He then receives lasting "rulership and dignity and kingdom".(Dan 7:13,14) This "son of man" is none other than Jesus Christ - the Messiah. God designated his own Son, Jesus, to be King of his "kingdom". When before the Pharisees, he told them that "the kingdom of God is in your midst".(Luke 17:21) What did this mean ? That he, as the future King of God's kingdom, was among them.
In addition, at Daniel 7, associate kings are brought to light, saying that "the kingdom and the rulership....were given to the people who are the holy ones".(Dan 7:27) Hence, Jesus does not rule alone. The apostle John saw this, saying that with Jesus' shed blood, he "bought persons for God out of every tribe and tongue and people and nation, and you made them to be a kingdom and priests to our God, and they are to rule as kings over the earth."(Rev 5:9,10)
At Revelation 14:1-3, John wrote: "I saw and look ! the Lamb standing upon the Mount Zion, and with him a hundred and forty-four thousand....who have been bought from the earth." Who is the Lamb spoken of here ? John the Baptizer identified Jesus as the "Lamb of God".(John 1:29) Mount Zion refers to heaven, for the apostle Paul wrote to the Hebrews that "you have approached a Mount Zion, and a city of the living God, heavenly Jerusalem."(Heb 12:22) Thus, Jesus, along with the 144,000 chosen or "holy ones", rule from heaven. Since heaven is it's seat, "the kingdom of God" is also called "the kingdom of the heavens".(Luke 8:10; Matt 13:11) No weapons, not even nuclear attacks, can reach and topple that heavenly government. It is unconquerable and will fulfill God's purpose for it.(Heb 12:28; Isa 55:10,11)
God's kingdom has laws and principles from God that govern it. Rather than unfairly restrict us, they benefit us.(Ps 19:7-11) Many are already benefiting from living by God's righteous requirements. For example, heeding the Bible's counsel to husbands, wives, and children improves our family life.(Eph 5:33-6:3) When we obey the command to 'clothe ourselves with love', our relationship with others improves.(Col 3:13,14) As we live by Scriptural principles, we also cultivate good work habits and a balanced view of money.(Prov 13:4; 1 Tim 6:9,10) Avoiding drunkeness, sexual immorality, tobacco, and addictive drugs helps one to safeguard their health.(Prov 7:21-23; 23:29,30; 2 Cor 7:1)
At Daniel 2:44, God had a "definite time" in which to "set up" his "kingdom", for it to go into operation, during the "days of those kings", which is our time period, human governments that would be existing as the "feet and the toes" of the "immense image", that are "partly of molded clay and partly of iron".(Dan 2:41-43) According to Daniel 7:22, there is a "definite time"("the stated-time", online Scripture4all interlinear) that the "holy ones took possession of the kingdom itself." The apostle Paul said that those "holy ones", "those that belong to Christ", would rule with Jesus as "kings and priests,(Rev 1:6) upon their resurrection to heavenly life during Jesus "presence" (1 Cor 15:23, 1 Thess 2:1, Greek parousia, not "coming" as in many Bibles).
This only touches the "tip of the iceberg" concerning God's kingdom. There is much more.