Exactly a century ago, J. Gresham Machen (1881-1937) in his book Christianity and Liberalism (1923) confronted Liberalism as an alternative system to biblical Christianity by way of exposing its deviating premises and deviated outcomes. Machen identified in Liberalism as another religion which – while using traditional Christian terminology – had completely re-signified it in terms of the spirit of the modern age and therefore abandoned the gospel. In Machen’s view, it is Liberalism that is the main threat to biblical Christianity, and it is against it that he focusses his attention. Roman Catholicism only gets a perfunctory mention that is nonetheless worth considering because it signals an important awareness of the more general context of yesterdays and today’s fronts where Christianity needs to develop its theological discernment.
1. Liberalism as Another Religion
The theological landscape around Machen is characterized by the pervasive infiltration of Liberalism in the Church. This is not a minor issue. To put it bluntly, the problem is that Liberalism is not Christianity at all. According to Machen, Liberalism is “a religion which is so entirely different from Christianity as to belong in a distinct category” (6). Machen interprets the liberal project in oppositional and confrontational terms with regards to Christianity. “With regard to the gospel itself, modern liberalism is diametrically opposed to Christianity” (47).
Machen’s analysis suggests an interpretation of the liberal project, i.e. the attempt at reconciling Christianity with the modern spirit, by rescuing certain general principles of religion and regarding them as the “essence of Christianity” (5 and 53). Even without directly quoting him, it is clear that Machen has in mind the seminal book by Adolph von Harnack (1851-1930), the champion of liberal theology in the generation preceding Machen, on the essence of Christianity. As a matter of fact, Harnack had sought to achieve a historical understanding of Christianity wherein its original essence could be separated from subsequent accretions that he understood as unwarranted dogma. He attempted to isolate this essence using a scholarly historical method that abjured many biblical traits of the Christian faith. The roots and the outcomes of this project are alien to the gospel. According to Machen, Liberalism “proceeds from a totally different root” (146) and “relinquished everything distinctive of Christianity” (6).
In a summary of the main issues at stake, here is how Machen sees the chasm: “Liberalism differs from Christianity with regard to the presuppositions of the gospel (the view of God and the view of man), with regard to the Book in which the gospel is contained, and with regard to the Person whose work the gospel sets forth. It is not surprising then that it differs from Christianity in its account of the gospel itself” (99). The divergence does not revolve around points of speculative theology but impacts “the whole of life” (146). Thus, the title of the book Christianity and Liberalism is meant to set the former over against the latter and vice versa.
2. Roman Catholicism as a Perversion
Gresham Machen agrees with the reaction against the liberal re-interpretation of the gospel as it was articulated in The Fundamentals, a series of 12 volumes published between 1910 and 1915 in which the tenets of the traditional Protestant consensus were defended. His assessment of Liberalism does not mean that Machen displays a manichean mindset, i.e. having a black and white picture of the situation in and around Christianity.
First, not all members of liberal churches are to be considered outside of Christian fellowship. For all his opposition to Liberalism, Machen readily admits that “some liberals, though perhaps a decreasing number, are true believers in a personal God” (50-51). He can distinguish between Liberalism as a theological system that is diametrically opposed to Christianity and individual liberal Christians who despite of their being part of liberal churches are nonetheless true believers in Christ.
Second, not all different theological traditions outside of the Reformed camp are to be considered as opposed to Christianity in the same way as Liberalism is. Machen’s approach is not sectarian, but discerning what is primary and what is secondary for the Christian faith. For example, “the premillennial view” is an error, but not a “deadly error” (41). There is still much ground based on the Bible and the great creeds of the Church that unites all Christians, regardless their eschatological positions. A similar evangelical eirenism is applied by Machen to differences of “opinion” on sacramental issues between Lutheran and Reformed branches of the Church (42) or on “the nature and prerogatives of the Christian ministry” that divide Anglicans from other protestants (42-43), or even on the “difference of opinion” between Calvinistic theology and Arminianism (43) on God’s sovereignty and human responsibility. Machen cannot be suspected of downplaying all theological issues, yet he argues that “true evangelical fellowship is possible between those who hold … sharply opposing views” (43). This is to say that his apologetic theology does not stem from an oppositional and separatist mindset, but from a discerning spiritual assessment.
At this point, Machen’s brief comments on Roman Catholicism can be properly evaluated. Whereas he has labeled Liberalism as another religion and has referred to intra-protestant debates on important yet secondary issues as differences of “opinion”, the relationship with Rome is marked by “division” (43). In Machen’s view, Rome represents a “perversion of the Christian religion”. No explanation is offered as to why this is so, but the theological reasons for the criticism are assumed as valid, even though not spelt out. Having said that, Rome’s perversion is of a different kind than naturalistic Liberalism: the latter “is not Christianity at all” (43).
Perhaps with a hint of superficiality, Machen acknowledges that the Roman Catholic Church maintains “the authority of Holy Scripture” and accepts “the great early creeds”. In his mind these commitments make biblical Christianity closer to Rome than Liberalism, even though “the gulf” between Rome and the Reformation is believed to be profound. I dare take this comment as superficial and not indicative of Machen’s usual theological acumen. The reason is that even Liberalism upholds a certain authority of Scripture and a certain interpretation of the early creeds. These two elements are not rejected as such but re-interpreted in such a way as to be annulled. In Roman Catholicism too, a certain authority of Scripture is affirmed but, at the same time, is undermined given the intertwined role attributed to tradition and the magisterium of the church that make Rome dismiss “Scripture alone” and therefore reject the ultimate authority of Scripture.
Moreover, Rome for sure pays tribute to the early creeds of the church, yet interprets them in an expansive way given, for example, its Mariological inflated doctrine and its cooperative view of salvation. If Rome thinks of its Mariology and ecclesiology as organically stemming from the creeds, it is evident that formal adherence to the creeds does not necessarily translate into a biblically faithful reception of them. The point is that the authority of Scripture and the importance of the creeds are never dismissed blatantly, both in Liberalism and in Roman Catholicism. Both traditions have their own way of paying lip service to them while not submitting to them. Machen is right when he argues that “Christianity is founded upon the Bible. It bases upon the Bible both its thinking and its life. Liberalism on the other hand is founded upon the shifting emotions of sinful men” (67). What he omits to say is that Roman Catholicism too is not founded upon the Bible alone and therefore stands in contrast with biblical Christianity at all points.
3. Machen’s Strengths and Limits
Whereas Machen displays a penetrating understanding of Liberalism, i.e. its anti-Christian ideological roots and its pernicious outcomes, he does not show the same degree of doctrinal familiarity with Rome’s theological system. His comments on Roman Catholicism are therefore only perfunctory given also the fact that it is not the topic of his book. According to him the “chief modern rival of Christianity is liberalism” (45). Notice: the chief, not the only one. Christianity has other rivals around it and Roman Catholicism is one of them, not presenting exactly the same danger, but close to it.
Beside these brief annotations, there are other points that need to be highlighted in Machen’s theological argument. They show how his interpretation of Liberalism may fit Roman Catholicism too. For example, while discussing the entrance of paganism into the church in the name of Christianity, he maintains that “Modern liberalism is like the legalism of the middle ages, with its dependence upon the merit of man” (151). Here Liberalism is associated with the insistence upon human merit as a legacy of the Middle ages. Yet the true representative of it is Rome with its cooperative and synergistic view of salvation embedded in its sacramental system. Again, Machen argues that modern liberalism has lost the consciousness of sin and has developed a “supreme confidence in human goodness” (55). For sure, these are features of Liberalism, but present-day Roman Catholic theological trends are progressively underlining a similar reliance on human goodness as a distinguished mark of Rome’s anthropology and hamartiology. Finally, Machen refers to the liberal doctrine of the “universal fatherhood of God” (53) and “the brotherhood of man” (133) which liberalism considers as the essence of Christianity. True. In our contemporary world, however, there is no religious institution more committed than Roman Catholicism to universal fraternity and the universal fatherhood of God, as the recent encyclical “All Brothers” (2020) by Pope Francis indicates.
The same universalist deviations that Machen observed in Liberalism can be observed in Roman Catholicism too, thus making it a “perversion” of Christianity, as Machen rightly points out. This is to say that Machen’s views of Roman Catholicism are limited and selective in scope, in need of more in-depth treatments that would nonetheless follow his theological approach to modern rivals of biblical Christianity.
After a century Christianity and Liberalism is as theologically sharp as it was then. Its analysis of the old Liberalism applies to the new liberal developments as well. While being aware of the “perversion” of Roman Catholicism, it lacks the same cutting edge in addressing what is at stake with Rome’s gospel. It is as if Machen sees the problem of Roman Catholicism but it’s not his main target nor the most severely perceived challenge. In celebrating this landmark book for evangelical theology, one can appreciate its strengths and its limitations which call for an on-going evangelical engagement with the flaws of Roman Catholicism and the need for a biblical reformation of its doctrines and practices.
Christianity and Liberalism (New York, NY: The Macmillan Company, 1923). I am following the new edition: Grand Rapids, MI: Eerdmans, 2009. The number of pages will be reported directly in the main text.
 For my interpretation of Machen, I mainly rely upon George M. Marsden, “Understanding J. Gresham Machen”, Understanding Fundamentalism and Evangelicalism (Grand Rapids, MI: Eerdmans, 1991) pp. 182-201; Terry Chrisope, Toward a Sure Faith. J. Gresham Machen and the Dilemma of Biblical Criticism (Fearn: Christian Focus, 2000) and D.G. Hart, Defending the Faith. J. Gresham Machen and the Crisis of Conservative Protestantism in Modern America (Phillipsburg, NJ: Presbyterian & Reformed Publ. Co., 2003).
 Adolph von Harnack, Das Wesen des Christentums (1900); What is Christianity, trans. T.B. Saunders (New York, NY: G.B. Putman’s Sons, 1901).
 For Machen’s views on Roman Catholic political and cultural stances in his time, see D.G. Hart, Still Protesting. Why The Reformation Still Matters (Grand Rapids, MI: Reformation Heritage Books, 2018) pp. 162-164. For a Roman Catholic rebuttal of fundamentalist criticism of Roman Catholicism (which is not necessarily descriptive of Machen’s approach), see Karl Keeting, Catholicism and Fundamentalism. The Attack on “Romanism” by “Bible Christians” (San Francisco, CA: Ignatius Press, 1988).
 “Encyclical Letter Fratelli Tutti of the Holy Father Francis on Fraternity and Social Friendship” (2020): https://www.vatican.va/content/francesco/en/encyclicals/documents/papa-francesco_20201003_enciclica-fratelli-tutti.html (accessed 16/02/2022).