What is the difference between postmillennialism and amillennialism? Sam Storms answers this along with a little history on the term “amillennialism.” This excerpt comes from his book Kingdom Come.
“I should first point out that prior to the twentieth century ‘amillennialism’ was not a term even in use among Christians. All amillennialists were called postmillennialists. This isn’t difficult to understand, insofar as amillennialists also affirm that the second coming of Christ occurs after (‘post’) the millennial kingdom. All amillennialists also agree that the term itself is of recent origin, although they are insistent that the doctrine to which it points is as ancient as the church itself. Jack Van Deventer points out that the International Standard Bible Encyclopedia (ISBE) had no reference for the word amillennialism in is 1915 and 1929/1930 editions. Some have insisted that the term was coined by Abraham Kuyper (d. 1920). Van Deventer believers the earliest use of the label should be attributed to dispensationalist Charles Feinberg in the title to his book, Premillennialism or Amillennialism, published in 1936. In any case, the term amillennialism was likely employed to differentiate its view from that of the more optimistic version of postmillennialism.
Some have jokingly referred to postmillennialism as ‘optimistic amillennialism’ or to amillennialism, conversely, as ‘pessimistic postmillennialism’! There is a measure of truth in this, for the critical question is whether or not one conceives of the church age as a time of ever-increasing gospel prosperity. Will Christianity experience both worldwide growth and influence, such that it gradually becomes the rule rather than the exception among the majority of mankind? Amillennialists say No. Postmillennialists say Yes.
Thus what is really at stake is the question of the future prospects for the kingdom of God that is already established on the earth. As far as postmillennialism is concerned, its essential distinctive, its sine quo non, is its expectation of gospel prosperity for the Church during the present age. Whatever else may be said about it, postmillennialism requires a consistent and confident, biblically grounded assurance that the gospel will be victorious around the globe before the second coming of Christ and the end of the age. Clearly, then, postmillennialists affirm that the Church of Jesus Christ will prosper, in this age, both in terms of numerical size and spiritual vitality. Through the gracious power of the Holy Spirit, the vast majority of the human race will be brought to faith in Christ, resulting in worldwide obedience to his kingdom rule. The postmillennial expectation, therefore, is for a Christian world comprised of explicitly Christian nations and peoples.” (374-75)
Storms concludes this chapter saying: “I want to believe postmillennialism is true. The notion of a progressive and ultimate triumph of the gospel within history itself such that when Jesus returns he finds a truly Christianized cosmos is profoundly appealing. But as of the publication of this book, I am not yet convinced. I remain an amillennialist.” (384)