Isn’t Postmillennialism Really Liberalism?
In order to answer this question, we have to define the two terms: “postmillennialism” and “liberalism.” First, what is postmillennialism? Postmillennialism is the belief that, before Christ returns, by the power of the Spirit, the kingdom of Jesus Christ will grow to enjoy a period of prosperity and growth throughout the world through the Church’s faithfulness in fulfilling the Great Commission. In general, the nations of the world will be converted (cf. Genesis 12:3; Psalm 22:25-31; Isaiah 11:9; etc.). Reconstructionists go a step further to say that the converted nations will seek to order their common social and political life according to the Word of God in Scripture (cf. Isaiah 2:2-4; 65:17-25; etc.).
To put it more simply, postmillennialism is the affirmation that Christ “must reign until He has put all His enemies under His feet” (l Corinthians 15:25). While men will always be sinners until Jesus returns, the Spirit will progressively turn the hearts of men away from unbelief and sin to righteousness and faith. Postmillennialism does not teach that a sinless utopia will be established before Christ returns, but simply insists that where sin abounded, grace much more abounded (Romans 5:20).
Second, what is “liberalism”? At the heart of theological liberalism are several important departures from orthodox Christianity. Liberalism denies that the Scriptures are true and accurate in every particular. The liberal may view the Scriptures with admiration, and even say such things as “the Scriptures are the source of all authority,” but the liberal does not believe that the Scriptures are inerrant. Thus, liberals have historically attempted to explain (away) those portions of Scripture that they find troubling, and especially the miracles of Jesus. One liberal scholar “explained” Jesus’ raising of Lazarus by saying that Lazarus was not dead, but buried prematurely. Jesus knew this, though no one else did. So, Jesus did not raise Lazarus; He just woke him up. (This is why liberalism is asleep!)
Liberalism not only tends to explain all the miracles of Scripture in a naturalistic and rationalistic manner, but also explains the growth of the kingdom in the same way. In liberal theology, the growth of the kingdom is not seen as the product of the Holy Spirit’s supernatural renewal of men and women. Instead, the kingdom in liberal theology is seen as an ethical community that grows in history as the result of inherent evolutionary forces, and the inherent dignity and goodness of man. Thus, liberal optimism about the kingdom of God is opposite from the orthodox postmillennial position. The postmillennialist does not put his hope in man’s inherent goodness, but in the power of the Spirit to transform sinners into saints.
Even the briefest glance at the historical background of postmillennialism shows that it is not at all identical with liberalism. Augustine (354-430), bishop of Hippo, was without question the most influential of the early fathers and was arguably the most influential thinker and writer in West European intellectual history. Augustine’s eschatology is complex, but the note of optimism and progress is not absent. It appears that Augustine believed that progress in the knowledge of God would eventually lead to an earthly golden age. Conservative historian Robert Nisbet concludes that “there are grounds for belief that Augustine foresaw a progressive, fulfilling, and blissful period ahead, on earth, for humanity – prior to entry of the blessed into heaven.”
The Reformer John Calvin (1509-1564) likewise emphasized the victorious character of the kingdom of God. Commenting on 2 Thessalonians 2:8, Calvin writes,
Paul, however, intimates that Christ will in the meantime, by the rays which he will emit previously to his advent, put to flight the darkness in which antichrist will reign, just as the sun, before he is seen by us, chases away the darkness of the night by the pouring forth of his rays.
This victory of the word, therefore, will show itself in this world…. He also furnished Christ with these very arms, that he may rout his enemies. This is a signal commendation of true and sound doctrine – that it is represented as sufficient for putting an end to all impiety, and as destined to be invariably victorious, in opposition to all the machinations of Satan.’
Calvin thus believed that the kingdom was already present, and that it was triumphantly advancing to a great climax.
This victorious outlook was embodied in the 1648 Westminster Larger Catechism. The answer to question 191 states:
In the second petition, (which is, Thy kingdom come,) acknowledging ourselves and all mankind to be by nature under the dominion of sin and Satan, we pray, that the kingdom of sin and Satan may be destroyed, the gospel propagated throughout the world, the Jews called, the fullness of the Gentiles brought in; the church furnished with all gospel-officers and ordinances, purged from corruption, countenanced and maintained by the civil magistrate: that the ordinances of Christ may be purely dispensed, and made effectual to the converting of those that are yet in their sins, and the confirming, comforting, and building up of those that are already converted: that Christ would rule in our hearts here, and hasten the time of his second coming, and our reigning with him for ever: and that he would be pleased so to exercise the kingdom of his power in all the world, as may best conduce to these ends.
Jonathan Edwards (1703-1758) expected an even fuller outpouring of the Spirit in the future, so that “the gospel shall be preached to every tongue, and kindred, and nation, and people, before the fall of Antichrist; so we may suppose, that it will be gloriously successful to bring in multitudes from every nation: and shall spread more and more with wonderful swiftness.” This great outpouring of the Spirit will be met with vicious opposition. Though Edwards admitted that “we know not particularly in what manner this opposition shall be made,” one thing was certain: “Christ and his church shall in this battle obtain a complete and entire victory over their enemies.”
As a result, Satan’s kingdom will be fully overthrown. In its place, Christ’s kingdom will be “set up on the ruins of it, everywhere throughout the whole habitable globe.” These events will usher in a new era for the church. The church will no longer be under affliction, but will enjoy undiluted success. Edwards believed that “this is most properly the time of the kingdom of heaven upon earth.” The Old Testament prophecies of the kingdom will be fulfilled in this era. It will be a time of great Spiritual knowledge, holiness, peace, love, and orderliness in the church. All of this would be followed by the great apostasy and the second coming of Christ.
This view of the kingdom was adopted by many of the leading nineteenth-century theologians in the United States, especially those in Calvinistic seminaries. Princeton’s Charles Hodge (1797-1878) wrote that “before the second coming of Christ there is to be a time of great and long continued prosperity.” Hodge referred to one theory that claimed that this period would last 365,000 years, but he remained cautious: “During this period, be it longer or shorter, the Church is to enjoy a season of peace, purity, and blessedness as it has never yet experienced.” Hodge claimed that “the prophets predict a glorious state of the Church prior to the second advent” because “they represent the Church as being thus prosperous and glorious on earth.”
The great Southern theologian Robert L. Dabney (1820-1898) concurred with Hodge’s views. Before the second coming, Dabney taught, the church would preach the gospel to all nations and would see “the general triumph of Christianity over all false religions, in all nations.” Benjamin Breckinridge Warfield (1851-1921), the great conservative theologian of Princeton, echoed the same themes of victory. Commenting on Revelation 19, he wrote,
The section opens with a vision of the victory of the Word of God, the King of Kings and Lord of Lords over all His enemies. We see Him come forth from heaven girt for war, followed by the armies of heaven… What we have here, in effect, is a picture of the whole period between the first and second advents, seen from the point of view of heaven. It is the period of advancing victory of the Son of God over the world.
Postmillennialist eschatology is certainly not the same as theological liberalism. Identifying postmillennialism with liberalism cuts both ways. Most cults are premillennial!
 Robert Nisbet, History of the Idea of Progress (New York: Basic Books, 1980), p. 67.
 Quoted in Greg Bahnsen, “The Prima Facie Acceptability of Postmillennialism,” Journal of Christian Reconstruction III, ed. Gary North (Winter 1976-1977), p. 70. Emphasis was added by Dr. Bahnsen.
 3. Edwards, “History of Redemption,” in The Works of Jonathan Edwards, 2 vols. (Edinburgh: Banner of Truth Trust,  1974), vol. 1, p. 606.
 Ibid., pp. 607-8.
 Ibid., pp. 609-11.
 Charles Hodge, Systematic Theology, 3 vols. (Grand Rapids, MI: Eerdmans, 1986
[1871-1873]), vol. 3, pp. 858-59.
 Robert L. Dabney, Lectures in Systematic Theology (Grand Rapids, MI: Zondervan,  1976), p. 838.
 B. B. Warfield, “The Millennium and the Apocalypse,” Biblical Doctrines (New York: Oxford University Press, 1929), pp. 647-648.