Although we cannot know the day nor the hour of His second coming, we can know and should realize that it is to be a pre-Millennial, and not a post-Millennial coming. That is, He is coming before and not after the 1,000 years reign of Christ on earth, Rev. 20:1-7.
The theory of post-Millennialism is dangerous because it would have us substitute man and his works for the work of God. The theory is that man ushers in the Millennium through his own efforts, and secures his own happiness without the grace of God. This school of interpreters believes that the organized church is to prosper and extend its scope until the whole world is converted, thus bringing in the Millennium, when in reality, the church is less near the accomplishment of this than in the time of the apostles.
It further teaches that Christ could not, or would not come back to earth while the world is sinful and that, when it is converted, men will invite Christ back to the world to reign. This certainly is not the teaching of Scripture. The purpose of this dispensation is not the conversion of the world, for all will not believe. It is the calling out of a people to serve as kings and priests with Christ during the Millennium and forever, Rev. 1:5, 6; 5:9, 10; 20:4; 22:5. The above passages under point 1 certainly do not harmonize with the idea of a converted world or picture such at Christ’s coming. Revelation Expounded.