Jesus was preoccupied—even obsessed—by one overarching concept. Yet most Christians wouldn’t include this concept in a summary of Christian doctrine.

Jesus taught about this concept more than salvation, grace, money, neighborly love, legalism, or the arrival of the Spirit. In fact, he probably teaches about it more than all those—combined. He says preaching it is “the purpose” of his mission (Luke 4:43). And he assumes it’s what Nicodemus wants to talk about in their secret meeting. Furthermore, this concept is the focus of his most famous teachings: the Parable of the Sower, the Lord’s Prayer, and the Sermon on the Mount. Yet, historically speaking, most Christians and experienced theologians hardly mention it.

Today, both critical and conservative Bible scholars (who rarely agree on much) concur that this teaching is “the central theme” of Jesus’ public teaching. Yet the majority of his followers wouldn’t mention it in a summary of Christian doctrine.

The father of twentieth-century missions, E. Stanley Jones, wrote, “The three historic creeds summing up Christian thought and doctrine [the Apostles’, Athanasian, and Nicene Creeds] among them mention once what Jesus mentioned a hundred times.”[ref]The Unshakable Kingdom and the Unchanging Person (1972), p. 30.[/ref] Only the Nicene Creed, as amended in 381 ad, mentions in passing that Jesus’ “kingdom shall have no end.”

More than any other subject, Jesus taught about the kingdom of God. The kingdom is mentioned more than salvation, the Spirit, legalism, grace, and money combined. What’s more, Jesus announces it as the chief focus of his mission. After returning from the desert to preach publicly, he proclaims, “Repent: for the kingdom of heaven is at hand” (Matthew 4:17).[ref]Unlike the other three gospels, Matthew refers to the “kingdom of heaven” (rather than the “kingdom of God”) to circumvent writing the word “God” which could have offended Matthew’s primary audience, the Jewish people.[/ref] Early in the gospel of Luke (4:43), he announces that he must “preach the kingdom of God … for I was sent for this purpose.”

Several obstacles hinder our understanding of the kingdom. Therefore, let us explore the complex reality of the kingdom by looking first at two riddles surrounding it, then at who is opposing it, and finally, at how we can go about living in it within the present confines of a corrupted world.

The first riddle is this: When is the kingdom? A straw-poll would probably reveal the majority of people expect the kingdom to arrive in the future. Yet Jesus often indicated that the kingdom had arrived. He states that the kingdom “is at hand” or “has come near” at the beginning of his teaching. He tells the Pharisees that His power over demons is evidence that “the kingdom of God has come upon you” (Luke 11:20). He says that John the Baptist marks the end of the era preceding the kingdom: “Since that time the gospel of the kingdom of God has been preached, and everyone is forcing his way into it” (Luke 16:16). In other words, Jesus is clear: the kingdom is present.

Yet on other occasions, Jesus says the kingdom has not fully arrived. He prays to the Father, “Your kingdom come,” implying it hasn’t yet. He tells Pilate that his kingdom “is not of this world.”[ref]“Not of this world” is the typical translation of John 18:36 found in most older English versions of the Bible. The full translation reads, “My kingdom is not of this world. If My kingdom were of this world, then my servants would be fighting” (NASB). But some newer translations (for example, the Revised Standard Version, 1946) do a better job of recognizing the dynamic use of the Greek word basileia—translated “kingdom” in older Bibles. Newer versions translate basileia as “kingly power” or “kingship,” thus reading, “My kingship is not of this world; if my kingship were of this world, my servants would fight, that I might not be handed over to the Jews; but my kingship is not of this world” (RSV). In these translations, the meaning is shifted from the timing of the kingdom to the nature of Jesus’ authority. In other words, Jesus’ servants will not fight because his “kingship” is not upheld by violence. His kingdom is of a completely different order than Pilate’s.[/ref] And in the Sermon on the Mount, a sort of outline of the kingdom, Jesus casts some beatitudes in the future: Those who mourn shall be comforted. The meek shall inherit the earth. Those who hunger for righteousness shall be filled.

So, when is the kingdom? Has it arrived, or does it remain in the future? The answer is both. Theologians have coined a few phrases to describe this accordion-shaped timeline. The kingdom is “now-but-not-yet”; Jesus announced the “presence of the future.” In other words, the bridegroom has arrived, and the celebration has begun; but the marriage will not take place until the end of time. As G. Eldon Ladd writes, “Jesus taught a present fulfillment in the setting of future consummation” (The Presence of the Future [1974], p. 123).

Jesus announced a new age, an alternative to the kingdoms of this world and this age. His resurrection served as a promissory note (in I Corinthians, “first fruits”) for a kingdom that had arrived but was not yet full.

The now-but-not-yet nature of the kingdom mirrors the engaged-but-not-married metaphor that Jesus frequently used to describe his relationship to his disciples. In Jesus’ day, a bridegroom would often construct a room onto his father’s house where he and his future wife would live after the marriage. Jesus alludes to this custom when speaking to his disciples for the last time:

In my Father’s house there are many dwelling places [or rooms]; if it were not so I would have told you; for I go to prepare a place for you. If I go and prepare a place for you, I will come again and receive you to Myself, that where I am, there you may be also. (John 14:2-3)

Both the kingdom and the marriage have begun. But neither is complete. Neither is fully arrived. We live between the promise and the fulfillment.

The second riddle that clouds our understanding is this: Jesus never defined the kingdom of God. He illustrated it with stories (“the sower and the seed”). He alluded to its nature (“a divided kingdom cannot stand”). He used metaphors to describe it (“pearl of great price”). But he never defined it.

Instead of defining the kingdom, Jesus used sayings and stories to paint a picture of a single but complex reality. This method can be compared to Claude Monet’s series of cathedral paintings: Monet painted the Rouen Cathedral over thirty times, each from a different angle in different light. The subject is the same even though the appearance varies.

Despite this stippled picture, we can see a whole: According to Jesus and the apostles,[ref]For brevity’s sake, I’ve concentrated on the Gospels instead of Paul’s teaching even though Paul also emphasized the centrality of the kingdom. He exhorts disciples in Asia Minor by saying, “Through many tribulations we must enter the kingdom of God” (Acts 14:22). The book of Acts closes, explaining that Paul spent two years in Rome, “preaching the Kingdom of God.” Paul doesn’t use the phrase as frequently as the Gospel writers, presumably because it was a Hebraic phrase that would be obscure to Gentile hearers.[/ref] the kingdom of God is a present reality that foreshadows a future time when God will rule completely. Entrance to the kingdom begins in the quiet reaches of the heart. And the ethical imperatives of the kingdom—to love God, neighbors, and enemies—are lived in anticipation of a time when wrongs will be made right and the True Judge will assume the throne.

But why did Jesus not simply supply this meaning? Instead of clearly articulating the nature of the kingdom, he daubed, hinted, and told stories. Why not simply define the kingdom?

The history of first-century Israel provides at least one good reason. In short, Jesus didn’t need to define the kingdom because he was born into an ongoing argument about the kingdom. Before he began preaching, Israel was engaged in a debate over the kingdom.[ref]The “Son of Man” vision in Daniel 7 appears to be a popular topic of conversation among the post-exilic Jews living during Jesus’ life. While exiled under Babylonian rulers, Daniel sees four “beasts” (presumed to be pagan nations) who oppress the people of Israel until judged by God. Although none of the beast-kingdoms are identified, some of Jesus’ contemporaries interpreted the last of these beasts as Rome—the final “beast” oppressing Israel.[/ref] Some Jewish sects anticipated the restoration of the house of David; these sects tended to expect a flesh-and-blood kingdom that would overthrow Roman rule. Other sects “lay more emphasis on the supernatural-transcendent character of the great time of salvation” and believed in a transcendent kingdom ruled by a spiritual Messiah.[ref]See Herman Ridderbos, The Coming of the Kingdom (1962).[/ref]

Since everyone around him believed a kingdom would soon arrive, Jesus didn’t need to define the kingdom. Instead, he spoke in a mosaic of metaphors, similes, and stories that corrected and amplified rival accounts of the kingdom.

And what was his mosaic-picture of the kingdom? His picture defied expectations. Instead of a powerful Jewish state (which the Pharisees hoped for), Jesus taught a peaceful kingdom that began, not in violent rebellion (which the Essenes hoped for) but in the quiet of men’s hearts. According to Jesus, the kingdom is “a treasure hidden in a field” and a “pearl of great price.” When the kingdom is found, men sell all they have to buy it (Matthew 13). But although the kingdom would begin in the secret places of men’s hearts, it would not remain confined to private spirituality. Once planted, the seed would grow from “the smallest of seeds” to become “larger than the garden plants and becomes a tree, so that THE BIRDS OF THE AIR COME AND NEST IN ITS BRANCHES” (Matthew 13:32).

At first, the scribes and Pharisees resisted Jesus’ account of the kingdom of God. Jesus directed his harshest words at them, saying, “you shut up the kingdom of heaven from men; for you do not enter in yourselves, nor do you allow those who are entering to go in” (Matthew 23:13). Unlike the scribes and Pharisees, one must become “like a child” to enter the kingdom (Mark 10:15). Prestige, external rectitude, and wealth hold no value. Instead, the leader of the kingdom values love, service, and humility above all.

The scribes and Pharisees represented but one slice of the broad opposition to Christ’s kingdom. As the gospel moved out from Israel, it would be opposed by a world-system. According to Paul, the kingdom of God is opposed not just by false religionists but by “the world” and “this age” (in Greek, kosmos and aeon). Paul imbues these Greek words with a broad portent of evil. He tells believers, “you once walked according to the course of this world [kosmos], according to the prince of the power of the air” (Ephesians 2:2). Yet, Jesus “gave Himself for our sins, so that He might rescue us from this present evil age [aeon]” (Galatians 1:4).

The kingdom of God is an alternative to a corrupted world. Like flowers in the snow, the presence of the kingdom can melt through the icy overlay of ignorance and vice. “An ordinary street scene,” wrote theologian Louis Berkhof, “such as an ambulance stopping all traffic because one wounded man must be transported, is the result of the coming of the Kingdom … Yet these are the crocuses [daffodils] in the winter of a fallen world.[ref]As quoted in The Search for a Christian America by Mark A. Noll, Nathan O. Hatch, and George M. Marsden (1989), p. 45.[/ref]

Seamus Deane’s novel Reading in the Dark (1996) paints a picture of how the kingdom serves as an alternative to the system of this world. In the novel, an earnest young priest tells a story to a classroom of Irish boys about to graduate. The priest’s story is about a reckless man who injures a police officer; the conflict escalates when the police officer’s friends take revenge in the middle of the night. The battle spirals until no one remembers or cares how the violence started. “The whole situation,” the priest says, “makes men evil. Evil men make the whole situation.” This is the kingdom of this world.

But the boys have a choice. The priest tells the boys they are entering a world “of wrong, insult, injury, unemployment, a world where the unjust hold power and the ignorant rule. But there is an inner peace nothing can reach; no insult can violate, no corruption can deprave. Hold to that; it is what your childish innocence once was and what your adult maturity must become. Hold to that.”

Establishing and describing the kingdom of God was the central concern of Jesus’ life. His teaching, death, and resurrection initiated the kingdom that will be fulfilled at the end of time. Citizens of the kingdom extend its borders not by the violent overthrow of worldly powers but by extending the rule of Christ from the quiet reaches of their hearts into love and justice in their homes, neighborhoods, and societies.

Since Emperor Constantine decriminalized Christianity in 313 ad, the kingdom of God and the kingdom of man have commingled in the Western world. Sometimes the two kingdoms have existed in conflict, sometimes in tension, sometimes in peace. And during the ensuing two thousand years, the kingdom of God has helped share and shape many of the religious and social ideals of Western civilization.

Now we live in what philosopher Charles Taylor calls a “secular” age—an age that was deeply shaped by the ideals of Jesus’ kingdom yet is estranged from His metaphysical claims. This split complicates social and political life for Christians. Liberal democracy, human rights, and medical advances can be understood as imperfect yet worthwhile extensions of Jesus’ kingdom—and, thus, worth support. But can they thrive severed from their affinity with the humaneness and reverence implicit in Jesus’ kingdom? The question remains to be answered.

The upper story of our society (national politics, big business, large-scale media) dominates headlines. But these upper story headlines ought not distract followers of Jesus from seeking the kingdom of God locally—in the episodic beauty of everyday life. The kingdom extends its borders through forgiving insults, loving enemies, and hosting warm meals for our neighbors. Against such things there is no law.