In his book Unfamiliar Paths, evangelical missionary David Bjork recounts his journey away from an independent church-planting effort in France under the auspices of his own denomination and his decision to integrate himself instead into the local French Catholic parish as an evangelist. Bjork now promotes evangelical-Catholic cooperation in mission on the basis of what he considers “agreement over evangelical truths which are basic to salvation and on our common life in Christ”. Undergirding Bjork’s statement is the belief, shared by a growing number of evangelicals, that Roman Catholicism has undergone many positive theological changes since Vatican II, especially with what pertains to the core truths of the gospel. Anthony Lane, for example, argues that while many significant differences still remain, the Catholic-Protestant consensus on justification marks “an important milestone on the path towards full agreement”. Others like Donald Norwood go further, opining that the degree of confessional unity achieved by Protestants and Catholics is now so great that “the only church-dividing difference is the church itself”.
According to Italian theologian Leonardo De Chirico, however, evangelicals arrive at such conclusions because they tend to appraise Catholicism atomistically, namely, as a conglomerate of related but distinct loci rather than as a single coherent structure. In De Chirico’s estimation, the weakness of an atomistic approach is that it treats the various aspects of Catholic theology and practice as separate issues while overlooking the underlying logic that determines the specific form and content of each part. Consequently, evangelicals potentially err in professing unity with Catholics on the basis of agreement on doctrines like justification if they fail to discern the organic connections that inhere in Catholicism between those doctrines and others that they still find objectionable (e.g. Mariology, transubstantiation).
Bjork’s thinking seems to falter for precisely this reason. The axiom that drives his ecumenical missiology – “conversion is primarily ‘to Christ’ and not…to one particular church”  – would be incomprehensible to Catholics for whom, in the words of R.J. Neuhaus, “the act of faith in Christ and the act of faith in the Church are not two acts of faith but one”. As Monsignor Brunero Gherardini avers, the historic Catholic-Protestant dissension over justification hinges not merely on the relationship between grace, faith, and works but, more fundamentally, on the Catholic Church’s insistence to be the necessary mediator of justifying grace through sacraments rendered efficacious only by its episcopate. In other words, soteriological unity between evangelicals and Catholics is impossible without ecclesiological unity, because in Catholicism, ecclesiology is soteriology.
Necessary, therefore, is a way of assessing Roman Catholicism as a conceptual totality. In a statement based on the research of Leonardo De Chirico and entitled An Evangelical Approach Towards Understanding Roman Catholicism (full text), the Institute of Evangelical Formation and Documentation (IFED) in Padua, Italy reminds evangelicals that
Roman Catholicism is a complex reality. A global view of Catholicism, must take into account its doctrine, culture, and its institutions. It is a religious worldview which has been promoted throughout history by the ecclesiastical institution whose centre is in Rome. Although there is considerable diversity in its forms of expression, Catholicism is a basically unitary reality whose underlying tenets can be discerned. Any analysis which does not take in to account the fact that Catholicism is a system will fall prey to a superficial and fragmented understanding of the phenomenon.
What does such a systemic analysis capable of discerning the “unitary reality” of Roman Catholicism look like? IFED’s statement continues by explaining that
Catholicism’s starting point is the Thomist conception of the relationship between “nature” and “grace” into which is engrafted the idea of the Church as the extension of the Incarnation of the Son of God. Both of these themes can be presented with subtle diversity and with any number of interpretative variations, but by virtue of the fact that they form Catholicism’s ideological framework, they will always be found to be present. This basic orientation in its presuppositions explains why Roman Catholicism has no sense of the tragedy of sin, tends to encourage an optimistic view of man’s abilities, sees salvation as a process in which nature is made more perfect and justifies the Church’s role as a mediator between man and God.
The IFED statement identifies two principles as the foundation of all Catholic theology and practice: “the Thomist conception of the relationship between ‘nature’ and ‘grace’” and “the idea of the Church as the extension of the Incarnation of the Son of God”. The first principle, expressed by the famous dictum of Thomas Aquinas that “grace does not destroy nature, but perfects it”, posits a metaphysical continuity between the higher order of divine grace and the lower order of created nature such that the former can elevate the intrinsic capacity of the latter and thereby transform it into a recipient and conduit of salvation. As illustrated by the Catholic Church’s teaching on the converting power of the sacraments and on humanity’s innate ability to know God through natural reason, nature is optimistically construed as wounded by sin yet inherently capable of receiving, cooperating with, and even conveying salvific grace.
The second principle identifies the Catholic Church as the requisite mediator between nature and grace in virtue of its prolongation of Christ’s incarnation. As detailed in its official catechism (para.795), the Catholic Church holds that the totus Christus – the “whole Christ” – does not consist of Christ alone but of “Christ and his Church” that together “form…one and the same mystical person”. As such, the Catholic Church (para. 824, 1069) considers itself to be both the sanctified and the sanctifier, the means “in, with, and through” which “the work of our redemption is accomplished”. As the work of Avery Cardinal Dulles suggests, these two principles inhere in what various Catholic thinkers identify as the underlying Catholic premise of “sacramental mediation”: “sacramental” because grace perfects nature, and “mediation” because Christ accomplishes this nature-perfecting work through his ecclesial body that, in Ratzinger’s words, “causes him to be alive and present in the world”.
While noting the diversity of expression, the IFED statement contends that, given their constitutive role, these two principles can be discerned throughout the entire Catholic system and should therefore be employed for making accurate assessments. Although some express doubt about this, Gregg Allison vindicates the validity of IFED’s approach by demonstrating the dependency of virtually all Catholic theology and practice on these twin principles through an exhaustive study of its catechism. For example, the Catholic Church’s (para.1127-1129, 1987–1995) position on justification obtains from the belief that grace unlocks the intrinsic potential of humans to freely cooperate in their salvation (principle one) and that Christ dispenses this grace through the Church (principle two). Transubstantiation stems from the view that physical substances such as bread and wine can become means of communicating Christ’s body and blood (principle one) through the consecrating work of priests who act “in the person of Christ the head” (principle two) (para.1348–1353). The mediatorial role assigned to Mary, the saints, and the priesthood derives from the notion that human beings can be elevated on the nature-grace continuum (principle one) in order to participate with Christ in consummating his redemptive work (principle two) (para.874–896, 954-959, 963-975). Papal authority, arguably the cornerstone of the Catholic Church’s identity, likewise flows from these principles: since grace perfects nature, the pope can possess absolute authority over the Church; since he is the “Vicar of Christ”, the pope must possess absolute authority over the Church (para.881–883).
Though further examples could be multiplied, these seem sufficient to warrant three conclusions. First, a denial of Catholicism’s two principles would appear to undermine the vast majority of its theology and practice, either invalidating its peculiar elements or liberating universally affirmed doctrines from its idiosyncrasies. This suggests that, second, these principles have remained intact despite surface-level changes that would otherwise suggest a Catholicism more amenable to Protestant convictions. Third, evangelicals with historic Protestant commitments should probably not profess unity of faith with the Catholic Church. Insufficient seem even the most basic affirmations such as “Jesus Christ is Lord” or “we are justified by grace through faith because of Christ” (see, for example, Evangelicals & Catholics Together), for according to Roman dogma, Christ is Lord insofar as he rules through his papal episcopate, and he justifies by grace mediated through ecclesial channels deriving their efficacy ultimately from the Catholic Church (Christus Dominus, sec.1–2, Unitatis Redintegratio, sec.3). Contra evangelicals like David Bjork, cooperative evangelical-Catholic mission seems unwarranted since, in Catholic
teaching, conversion does not occur to solus Christus, as in historic Protestant theology, but to the totus Christus, namely Christ-as-mediated-by-the-Catholic-Church. In sum, the two principles that constitute the essence of Roman Catholicism appear to fundamentally oppose the sola-centred convictions of historic Protestantism, inasmuch as they give rise to the all-pervasive Catholic “and”: grace and nature, Christ and church, revelation and reason, Scripture and tradition, faith and works, etc. As Karl Barth astutely observed:
In all its shoots the theology which says “and” derives from one root. If you say “faith and works,” “nature and grace,” “reason and revelation,” at the appropriate place you logically and necessarily have to say “Scripture and tradition.” The “and” by which the authority of Holy Scripture is relativised in…Roman Catholicism…is only the expression, one expression, of the fact that already the majesty of God has been relativised in His fellowship with man. And in this primary relativising both are equally remote from the Reformation decision.
Is the Reformation over? Based on the preceding analysis, I would utter a loud Barthian Nein! The Reformation will not be over until the Roman Catholic Church abandons its fundamental principles and subjects itself to a radical renovation of its entire system on the basis of the five solas of the Reformation. That is to say, apart from a miraculous and sovereign outpouring of the grace of God through his Word in the power of the Spirit (which I absolutely believe he can do!), it seems to me that the Reformation is likely to continue for quite some time, until the day when the Catholic “and” becomes the Protestant “sola”.
 Bjork, D.E., 2014. Unfamiliar paths: the challenge of recognizing the work of Christ in strange clothing, 2nd ed. Pasadena: William Carey Library, p.6.
 Lane, A.N.S., 2002. Justification by faith in Catholic-Protestant dialogue: an evangelical assessment. London/New York: T&T Clark, p.231.
 Norwood, D.W., 2015. Reforming Rome: Karl Barth and Vatican II. Grand Rapids: Eerdmans, p.165.
 De Chirico, L., 2003. Evangelical theological perspectives on post-Vatican II Roman Catholicism. Bern: Peter Lang.
 Miller, P.M, 2013. Evangelical mission in co-operation with Catholics: a study of evangelical missiological tensions. Eugene: Wipf & Stock. p.103.
 Neuhaus, R.J., 2007. Catholic matters: confusion, controversy, and the splendor of truth. New York: Basic Books, p.36.
 Gherardini, B., 1997. Dal peccato alla grazia: la dottrina della giustificazione in un confronto cattolico-luterano. Florence: Le Lettere, pp.118-122.
 Dulles, A., 1987. The catholicity of the church. Oxford/New York: Oxford University Press, pp.3-8.
 Ratzinger, J., 2009. Credo for today: what Christians believe. San Francisco: Ignatius Press, p.193.
 Allison, G.R., 2014. Roman Catholic theology and practice: an evangelical assessment. Wheaton: Crossway.
 Barth, K., Bromiley, G.W. & Torrance, T.F., 2004. Church dogmatics: The doctrine of the Word of God, Part 2, London; New York: T&T Clark. p.557.