It is absolutely astounding how complex and misconstrued some folks have made the Biblical teaching on the kingdom of God. It is a major theme in Scripture, but let’s see if we can see it in its simplicity.
God prophesied His coming kingdom for centuries. The King of this kingdom would come from the tribe of Judah (Gen. 49:10), through the lineage of David (2 Sam. 7:12-16), to set up His kingdom during the days of the Romans kings (Dan. 2:44), and to rule as King at the same time He served as priest (Zech. 6:12-13; Heb. 8:4).
God began pinpointing the timing of His coming kingdom for four years before its establishment. John the forerunner, Jesus Himself and the twelve all went out preaching, “The kingdom of heaven is at hand” (Matt. 3:2; 4:17; 10:7). Jesus promised to build His church/kingdom and give “the keys of the kingdom of heaven” (Matt. 16:18-19), all to be fulfilled within the lifetime of His generation (Mark 9:1).
God established His kingdom on the day of Pentecost in Acts 2. He said the kingdom would come with power (Mark 9:1), in the city of Jerusalem (Luke 24:49), when the Holy Spirit came upon the apostles (Acts 1:8). All of this transpired in Acts 2.
God inspired New Testament writers to speak of the kingdom as being present (thus, in existence). Paul said that God “conveyed us into the kingdom of the Son of His love” (Col. 1:13). It was in existence! John told his readers he was their “brother and companion in the…kingdom” (Rev. 1:9).
The progression is obvious as one reads through Scripture. The coming of the kingdom was in the distant future (during the Old Testament prophecies). Then, it was closer in time (but still future) during the ministries of John and Jesus. Finally, it came into reality (in the present tense) in Acts 2. Writers of the N.T. epistles referred to the kingdom as being present, thus having been established prior to their writing.
Finally, God reveals the future of His kingdom. Already being in existence for nearly 2,000 years, what remains for the kingdom of our Lord? When Jesus returns and the end comes, “He shall deliver up the kingdom to God, even the Father” (1 Cor. 15:24). It is already here now; in the end, He will hand it over to His Father.
The kingdom is an integral part of God’s eternal scheme of redemption, and it is not the complex mystery man has made it out to be. Study these simple points, and then recall that Jesus specified the terms of entrance into His kingdom—one must be baptized (John 3:3-5).