Some key points backed up by lots of Scripture.
In the related post here is the basic definition of the kingdom of God:
Kingdom means his authoritative rule over a realm. And the realm can be in an individual’s heart, or it could be a visible and invisible, but universal realm. In other words, God has kingly authority to rule over and sustain the entire physical universe, and it means he rules over the invisible universe—the ideas and politics of all other worldly kingdoms, and Satan’s kingdom.
Now let’s begin at the beginning, from whom the kingdom flows: God.
I.. In what way is God a king?
In Num. 23:21, Balaam the-easily-bought prophet, said the shout of the king is among the people of Israel:
The Lord their God is with them;
the shout of the King is among them.
In Daniel 4:37, king Nebuchadnezzar calls God the king of Heaven, when the king’s sanity was restored, with the aid of Daniel.
Ps. 24:7-10 repeatedly calls the LORD the king of glory.
The psalmist says he is the great king (Ps. 47:2).
And these Scriptures teach us that the LORD rules over all the earth (2 Chron. 20:6; Ps. 99:1-2; Is. 52:7).
And a king must have a throne, so God too rules from his throne (1 Kings 22:19; Ps. 9:4, 7-8; Is. 6:1-3).
And Paul wraps up a chapter to his disciple Timothy by extolling God as the eternal, immortal, invisible king (1 Tim. 1:17).
From these verses and spiritual reality of God’s kingship flow the rich concept of king and kingship and kingdom.
Now let’s look at the Son’s kingship and reign.
II.. In what way is Christ king?
Let’s begin in the Old Testament and prophecies about him.
1.. His kingship was prophesied:
He will have a scepter, the emblem of kingship, for Gen. 49:10 says the scepter will not depart from Judah, and Christ comes out of that tribe. And Num. 24:17 teaches that a star and scepter will arise out of Israel. Yes, he will crush the enemies surrounding Israel, but this may be a double fulfillment or have multiple fulfillments, until the Messiah takes the scepter.
He will rule on David’s throne (Ps. 132:11-12; Is. 9:6-7; Jer. 33:17). Jesus is the son of David, and he fulfills these prophecies. He’s the one who makes David’s throne eternal.
In a Messianic psalm, which Jesus applies to himself (Matt. 22:43-45 // Mark 12:36-37 // Luke 20:42-44), he will rule at God’s right hand (Ps. 110:1).
After the kingdoms after the ones prophesied by Daniel, God will set up a kingdom that will never be destroyed; he will rule eternally (Dan. 2:44-45).
The Son of Man approached the Ancient of Days (God) and received from him authority, glory and sovereign power. He will rule with authority (Dan. 7:13-14).
The Messiah will rule as a shepherd (Is. 40:10-11; Ezek. 34:23-24; Mic. 5:2-4), and Jesus said he is the good shepherd (John 10:11).
The Messiah will rule wisely (Is. 52:13; Jer. 23:5).
He will rule with justice (Is. 32:1; Jer. 33:15-16).
He will rule humbly (Zec. 9:9).
He will function as a priest (Ps. 110:4; Zec. 6:12-13), and this was fulfilled (Heb. 8:1-13).
2.. His kingship is fulfilled in the NT:
Gabriel the archangel himself proclaimed to Mary that her son came to rule on David’s throne (Luke 1:32-33). In Acts 2:29-33, Peter offers a profound insight to the Jews of Jerusalem. David was dead and buried, and his body suffered decay. But Ps. 16:8-11 says that the king would not suffer that, so this is fulfilled in Christ, whose body never underwent decay.
The Magi asked where the king of the Jews was (Matt. 2:2). And the sign over the cross that he was the king of the Jews (John 19:19-21), and the author John seemed to have approved of the title.
After Jesus said he saw Nathaniel, not one of the twelve apostles, under a fig tree, possibly in a vision of sorts, Nathaniel proclaimed that Jesus was the king of Israel (John 1:49).
While Jesus stood before the Pilate the governor, the latter asked him if he was the king of the Jews. Jesus answered affirmatively (Matt. 27:11; John 18:37).
Zechariah prophesied that the king would enter Jerusalem on a donkey (9:9), as a humble king (Matt. 21:1-9).
Jesus has been raised up to sit at the right hand of God, where he rules far above all competing rule and authorities, powers and dominion and every name that is invoked. (Eph. 1:20-23). The author of Hebrews quotes Ps. 45:6-7 about the throne of God, and applies it to Jesus, thus making Jesus God who sits on an eternal throne (Heb. 1:3-8).
At the second coming with his angels the Son of Man will sit on his throne to judge the nations. He calls himself the King. He will sit as the Judge-King (Matt. 25:31-34).
And with kingships of God and his Messiah established, let’s look at the kingdom of God itself.
III.. When and how was the kingdom present?
1.. The kingdom was present in Jesus at the beginning of his ministry.
John the Baptist was the forerunner of Jesus, and he preached that it was near (Matt. 3:2).
Jesus launched the kingdom of God and proclaim that it had come (Mark 1:15).
2.. The kingdom was present during Jesus’s ministry.
Jesus preached the good news of the kingdom, which God’s right to rule over people’s lives and crush Satan under the Messiah’s feet and which brings restoration and reparations of the damage that humankind and Satan has wreaked on his earth (Matt. 4:23).
Parables describe how God controls it and causes its growth, which implies that we cannot cause its growth, other than just preach it (Matt. 13:11-52).
Jesus’s miracles proved he had kingly authority over diseases, which are outward signs of something that has gone wrong and needs repair (Luke 7:18-22).
Driving out demons proved he was shrinking Satan’s kingdom, and this will continue until God sweeps it aside forever (Luke 11:20).
Through Jesus the kingdom of God is present, which means he launches and sustains it to this very day (Luke 17:20-21).
3.. The kingdom was present at the end of his ministry.
It shines and comes through the death of Jesus, which means he disarmed ruling spirits through the cross (Luke 23:42-43; Col. 2:15).
It shines and comes through the resurrection of Jesus, which will inevitably conquer the final enemy: death (1 Cor. 15:20-25).
IV.. How do we enter the kingdom?
1.. God draws us into the kingdom.
We experience new birth or being born from above or regenerated by his Spirit (John 3:3).
We receive it as a gift from Jesus and cannot earn it (Luke 22:29).
2.. We must respond to his call out of our free will.
God is the one who calls us into his kingdom and glory, and we respond (1 Thess. 2:12).
In a word that is preached shallowly or hardly at all, we must repent of our sins (Mark 1:15).
In the Lord’s Prayer, we must pray for it (Matt. 6:10).
When God woos us and we follow Jesus, and we have to lay aside idols that hinder us (Matt. 19:21-24; Luke 9:61-62).
V.. How do we live in the kingdom?
1.. It must be our priority.
We must seek it first and his righteousness, and then everything else in life will be added to you (Matt. 6:33).
In answering the question of who is the greatest in the kingdom, Jesus called for a child and said we should live a life of childlike humility (Matt. 18:1-4).
2.. We live in the light.
Paul sets up a stark contrast between the kingdom of light and the Son whom God loves, and the dominion of darkness. We are transferred from the darkness and into the light of Christ (Col. 1:12-14). Apparently, God allows the dominion of Satan to still have a certain measure of authority and power, as long as people do not believe in Christ and his kingdom.
3.. We live in his righteousness.
Our righteousness must exceed that of the Pharisees—that is, we accept Christ’s righteousness (Matt. 5:20).
Jesus explains kingdom principles in the famous Sermon on the Mount, which boils down to closely following Jesus and his righteousness (Matt. 5:1-7:27).
He explains kingdom principles in the Sermon on the Plain, which boils down to following Jesus closely and his righteousness (Luke 6:17-49).
He explains the kingdom in many parables, which show how the kingdom of God is counter-cultural and overturns the ways of the world (Matt. 13:11-52; Matt. 18:23-35; Matt. 20:1-16).
VI.. How does the church respond to the kingdom?
1.. We preach and live it out.
The apostles preached the kingdom (Acts 8:12; 19:8; 28:23, 28).
We work for the kingdom (Col. 4:11).
While we do the works of the kingdom, like driving out demons, we must know Christ personally and do the will of his Father (Matt. 7:21-23).
God has chosen the poor of this world to inherit the kingdom of God, so don’t favor the rich and show contempt for the poor (Jas. 2:5).
2.. We endure difficulties and persecutions for it.
We may suffer persecution for it (Acts 14:22; 2 Tim. 4:16-18).
We persevere (persist or hang in there during tough times) in the faith (Acts 14:22; 2 Thess. 1:4-5).
3.. We live in the kingdom through the Spirit.
The kingdom offers a life of joy and peace in the Holy Spirit (Rom. 14:17).
The kingdom enables us to live a life free from sin’s domination (1 Cor. 6:9-11; Gal. 5:16-21; Eph. 5:3-5).
The kingdom through the Spirit enables us to produce fruit (virtues) of the Spirit (Gal. 5:21-23).
4.. But the church is not identical with the kingdom.
The kingdom of God existed before the birth of the church, and the church is imperfect because it is made up of imperfect people, while God’s active reign and rule is perfect. Therefore the church ≠ the kingdom. Instead, the kingdom creates the church, and in turn or in response, the church proclaims the kingdom.
The main point is that the kingdom creates and works through the church. They are not identical. The kingdom of God existed before the birth of the church, and the church is imperfect because it is made up of imperfect people, while God’s active reign and rule is perfect. People live in the realm of the kingdom, as noted under Question 4. They are not the kingdom itself, but are kingdom citizens. By analogy, citizens of the United Kingdom (UK) live in this kingdom, but are not the kingdom itself. When the ancient people of Israel lived in the kingdom of God (and earthly kings), they were kingdom citizens, but not the kingdom itself.
The Church ≠ The Kingdom.
So teachers who say the kingdom = converted people are not quite right.
Converted People = Kingdom Citizens
Kingdom = God’s Right to Rule over His Jurisdiction or Realm
His Jurisdiction or Realm = His Creation
VII.. Has the kingdom of God come in its full manifestation?
1.. This is the tension between his kingdom coming and his kingdom in the future.
Jesus prayed, “your kingdom come,” indicating that the kingdom had come, is coming, and will come (Matt. 6:10; Luke 11:2).
Some parables describe it as in the future (Matt. 25:1-34).
It comes at the return of Jesus (2 Tim. 4:1).
We will inherit it (Matt. 25:34; 1 Cor. 15:50; Jas. 2:5).
It is heavenly (2 Tim. 4:18; Heb. 12:26-28).
We will receive the kingdom (2 Pet. 1:11).
2.. It will soon come in complete power and glory.
The millennial kingdom is yet to come (Rev. 20:1-6).
We inherit it now in part, but it will be revealed in its fullness and glory and power and dominion at the return of Christ.
So how does this post help me know God through Christ more closely?
We live in the paradox of the already and the not-yet.
This means that the kingdom of God is already here (see Q’s V-VII). Jesus ushered and inaugurated it into time and history. However, Q VI says that the kingdom is not yet fully manifested, until the return of Christ.
This concept of the already-not-yet kingdom should clarify why your loved one died, after you prayed for him. But now he is experiencing the fullness of the kingdom and is completely healed. He will live forever. And when it is your time, you will see him again. He is not lost, but God has him.
Read the synoptic Gospels (Matthew, Mark, and Luke), if you want to learn more about the kingdom of God. Underline or circle the word every time it appears. Then jot down some notes. And then you can know God through Christ more fully. Or you can look up the references in this post, one at a time. Do both. Read the synoptics and look up these references.
Bible Basics about the Kingdom of God
ARTICLES IN THE SERIES
See the NIV Study Bible at that link.