In many ways, the teachings on the 1,000-year messianic kingdom in the Bible are like a stealth bomber in that they are designed to have a stealthy quality about them. In fact, discerning how and when Christ establishes his kingdom on this earth requires a great deal of synthesis of numerous obscure Old Testament passages, such as those found in Daniel. And, like a stealth bomber, God uses the book of Revelation as an apocalyptic form of literature to deliver the truth about Christ’s 1,000-year messianic kingdom. It seems that God intentionally wanted Revelation to be difficult to understand, particularly for unbelievers.
But why would God intentionally make the messianic kingdom difficult for Roman authorities to understand by putting a majority of the information in apocalyptic books such as Daniel and Revelation? The answer is because if the Roman authorities had easily understood these teachings about the messianic kingdom on this earth, they would have considered the future reign of Christ a serious threat to their empire. The messianic kingdom will be an earthly kingdom with all nations subservient to the Jewish Messiah. The Romans were understandably hypersensitive to any talk of a Jewish Messiah.
These were dangerous times to be speaking and writing about an earthly messianic kingdom in which Jesus of Nazareth would someday rule the world as King of kings and Lord of lords. And any proclamation of this coming kingdom by Jewish missionaries like Paul and the apostles would have surely caused the Roman authorities to react violently toward them and those who followed their teachings. Therefore, the apostles wisely focused on the eternal kingdom of heaven, which did not pose a real geopolitical threat to the Romans.