But each one in his own order: Christ the firstfruits, afterward those who are Christ’s at His coming. Then comes the end, when He delivers the kingdom to God the Father, when He puts an end to all rule and all authority and power. For He must reign till He has put all enemies under His feet. The last enemy that will be destroyed is death. (1Co 15:23-26 NKJ)
This passage rules out postmillennialism, for it has Jesus’ millennial rule operating in order to put down enemies. In a postmillennial scheme, the millennium happens after the world has been largely Christianized; the enemies have all pretty much been put down already. The premillennial likewise sees the rule of Christ happening after the enemies have all been defeated, and also has it happening after Christ’s second coming, in direct contradiction to this passage, which says that the rule of Christ happens until His second coming.
Both of these views suffer from externalizing the rule of Christ, making it something to be seen with the eyes. Jesus said, My kingdom is not of this earth, else would my servants fight. In addition, they misunderstand the nature of this rule as it works on the present age. It is the rule of the rod of iron, and a rod of iron is a weapon for punishing the disobedient. Psalm 2 sees the Messiah ruling with a rod of iron, dashing his enemies to pieces, until all are put under His feet, and according to 1 Corinthians 15 quoted above, the completion of the destruction of all Jesus’ enemies, by the power of the gospel, coincides with His second coming. Postmillennialism and premillennialism see this rule as exercising an already established reign of Christ over a conquered world, instead of seeing the millennial rule as the means by which that conquest is established, as Psalm 2 and 1 Corinthians 15 has it. It is the process of extending that rule over the world which is spoken of in Psalm 2 and 1 Cor 15. The end of the millennium, the second coming of Christ, comes at the point when that process is finished, culminating with the final confrontation between Christ and the devil spoken of in Revelation 19-20.
So amillennialism is our best understanding of the passage quoted above, as well as the other passages we have mentioned. The rule of Christ is the process by which He brings saints under His rule by His Spirit, and the process by which He casts down every false philosophy and religion erected in opposition to Him. Revelation 19-20 reveals a final time when Satan in his rage and defeat throws off every mask and disguise and comes against the people of God in open warfare and is finally destroyed forever by Christ in His triumphant return.
So we are now in a time of spiritual warfare, advancing the truth of the gospel against every false idea erected against it. We can do so confident of success, for it is Christ fighting the war through the power of His Spirit, working through His people.