The phrase "kingdom of God" is used over sixty times in the Bible, exclusively in the New Testament, and refers to a spiritual kingdom over which God is ruler. It is not a physical kingdom—Jesus told the Pharisees it could not be observed (Luke 17:20). The kingdom of God is a place that we are called to enter at any cost (Luke 18:17; Luke 18:29); it is also something that "comes near" to man (Luke 10:11). It is usually spoken of in terms of future glory, or of a place to which believers are headed after life on this earth is over. Many of Jesus' parables were about the kingdom of God and its subjects, as He tried to explain to His disciples what the kingdom of God is, and what it is like (Luke 13:18; Mark 4:26; Mark 4:30).
The Kingdom of God – What is it?
Jesus described the type of people to whom the kingdom of God belongs. It belongs to those who are "born of the Spirit" (John 3:3-5). They are like little children toward God, dependent and trusting (Luke 18:16-17). They are often people whom society has rejected—the poor, or those who have sinned or fallen short in some way (Luke 6:20; Matthew 21:31; 19:24). Jesus said it was easier for those people to get into the kingdom of God than it was for the rich or successful (Luke 18:24; Matthew 19:24). This fits with the gospel, which asks people to repent of their efforts to make it to God on their own (which is impossible) and to instead trust Him fully for salvation (Romans 3:19-26). The people who can already see their flaws clearly, and who are not blinded by worldly pride and vanity and wealth, find it much easier to enter the kingdom of God.
Jesus, His disciples and the apostles all preached about the kingdom of God, telling people to repent and believe (Luke 9:2; Acts 28:31; Acts 19:8). Paul preached that the kingdom of God "does not consist in talk but in power" and is not something that is inherited by flesh and blood, because that which is perishable cannot inherit that which is imperishable (1 Corinthians 4:20; 15:50). He was again pointing out that the kingdom of God is spiritual in nature—it is something that can only be accessed by God's Spirit, as Jesus told Nicodemus in John 3. Those who live according to the flesh and the world do not inherit the kingdom of God, and there is ample warning in Scripture against the practice of sin (1 Corinthians 6:9-10; Galatians 5:21).
The kingdom of God belongs to those who produce the fruit of the Spirit (Matthew 21:43; Galatians 5:22-23). It is an eternal kingdom, and though we sometimes suffer for it, in the end, the kingdom of God will provide a more than sufficient reward to those whose hope is placed there (Matthew 6:33; 2 Thessalonians 1:5-10; 2 Timothy 4:8).
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