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Is Ecumenism a Heresy?

Vying with the Declaration on Religious Liberty for the honor (or disgrace, depending on one’s theological outlook) of being the Second Vatican Council’s most doctrinally innovative document is its Decree on Ecumenism, Unitatis Redintegratio (UR). Those at both traditionalist and liberal ends of the Catholic spectrum have seen this Decree (with sentiments of glowering gloom and gloating glee respectively) as representing a significant departure from traditional doctrine. The latter, of course, emphasized Catholicism as the one true religion, to which separated Christians will simply have to return if ever unity is to be restored. In this short article I shall limit myself to a comparison between UR and the pre-conciliar papal document most frequently cited as being incompatible with it, Pope Pius XI’s 1928 encyclical on fostering true religious unity, Mortalium Animos (On Religious Unity). This encyclical set out the Catholic Church’s position regarding the fledgling movement for religious unity which had been gathering steam in liberal Protestant circles since the late 19th and early 20th centuries.

To compare these two magisterial documents, we first need to recall the distinction between a reversal of official Church policy, discipline or pastoral strategy, and a contradiction of doctrine. The former type of change has often taken place in the course of Church history, in response to changing circumstances. And in this practical, disciplinary respect, a comparison between MA and UR reveals an undeniable and very marked change of direction—indeed, practically a U-turn. Pius XI flatly forbade any Catholic participation in interchurch or inter-religious meetings and activities motivated by the desire for restoring Christian unity. Vatican II, on the other hand, authorizes and positively encourages Catholic participation in such activities (within certain limits). The modern Church has thus made a prudential judgment that the risks and dangers of indifferentism and confusion about the faith occasioned by such activities—perils strongly emphasized by Pius XI—are outweighed by the great good to be hoped for as the long-term result of ecumenism: gradual, better mutual understanding, leading to that unity which Christ willed for all who profess to be his disciples.

At the more fundamental level of doctrine, however, the short answer to the charge of contradiction between MA and UR is that what Pius XI condemned is by no means the same thing that Vatican II affirms. What, exactly, did Pope Pius condemn as false doctrine? Basically, the liberal Protestant theology that dominated ecumenical initiatives in the early 20th century. More specifically, this theology embodied—explicitly or at least implicitly—several specific theses censured by Pius XI.

Four Ecumenical Errors

(1) Early pan-religionists usually took a “lowest common denominator” approach: They envisaged a worldwide religious “unity” in which all would agree on a few basic beliefs while “agreeing to differ” on others. The pope observes that these religious liberals apparently “hope that all nations, while differing indeed in religious matters, may yet without great difficulty be brought to fraternal agreement on certain points of doctrine which will form a common basis of the spiritual life” (MA 2). This hypothetical “unity” in one “world religion” would of course include non-Christians of all types.

(2) Pius XI insisted that the above error involves another at a deeper level: denial of the very principle of revealed truth, which requires assent to God’s Word on his own authority. Contemporary pan-religious efforts operating on principle (1), the pope says,

presuppose the erroneous view that all religions are more or less good and praiseworthy, inasmuch as all give expression, under various forms, to that innate sense which leads men to God and to the obedient acknowledgment of his rule. Those who hold such a view are not only in error; they distort the true idea of religion, and thus reject it, falling gradually into naturalism and atheism. To favor this opinion, therefore, and to encourage such undertakings, is tantamount to abandoning the religion revealed by God. (MA 2)

This idea that all religions are just varying (and fallible) human expressions of a natural religious impulse or instinct was one of the fundamental errors of that modernism which had been so recently condemned by Pope St. Pius X.

(3) Turning from the inner nature of faith to outward forms of visible organization, Pius XI found another related error. In those initiatives limiting the quest for unity to those who already professed faith in Christ—what the Church today calls “ecumenism” as distinct from “inter-religious dialogue”—the pope discerned a false ecclesiology (theological understanding of the Church). For the visibly united “Christian church” that these liberal Protestant ecumenists dreamed of would be “nothing more than a federation of the various Christian communities, even though these may hold different and mutually exclusive doctrines” (MA 6).

(4) The pope pointed out that such an ecclesiology in turn involves the related idea that the unity which Christ prayed for—ut unum sint —”merely expressed a desire or a prayer which as yet has not been granted. For they [the contemporary ecumenists] hold that the unity of faith and government which is a note of the one true Church of Christ has up to the present time hardly ever existed and does not exist today. . . . [I]t must be regarded as a mere ideal” (MA 7).

Before looking at UR in the light of these condemned ideas, we can consider another common complaint. Traditionalist critics often claim that UR leaves the key concept of ecumenism dangerously undefined. I suspect this concern arises from a faulty translation in the common Flannery edition of the documents, which has the Council merely “indicating” what “the ecumenical movement” involves. A more faithful translation of the opening of UR 4’s second paragraph, bringing out its character as a definition, would be this: “The term ‘ecumenical movement’ is understood to mean (Per ‘motum oecumenicum’ intelleguntur) those activities and initiatives which are encouraged and organized, according to the various needs of the Church and when suitable occasions arise, in order to promote the unity of Christians.” The Council then makes this definition more precise by setting out the kinds of “activities and initiatives” it has in mind: (a) avoiding all misrepresentations of separated Christians’ beliefs and practices; (b) dialogue between scholars of different denominations for the purpose of better mutual understanding; (c) a more extensive collaboration in carrying out duties toward the common good recognized by “every Christian conscience”; (d) meeting for common prayer, where this is permitted; and (e) renewing and reforming the Church herself in faithfulness to Christ’s will. It seems clear enough that while (b), (c), and (d) do indeed relax the disciplinary prohibitions of MA, none of these five points contradicts any doctrinal truth laid down by Pius XI in his encyclical.

The Decree: No Error Here

Now we can go on to consider UR in the light of the four above-mentioned doctrinal errors reprobated by Pope Pius:

(1) Does Vatican II adopt a “lowest common denominator” approach to “balance” unity and truth? Not at all. Unitatis Redintegratio 3 affirms that while the separated brethren have many elements of truth, God’s will is that they all come to that plenitude which can be found only in Catholicism:

For it is through Christ’s Catholic Church alone . . . that the fullness of the means of salvation can be obtained. It was to the apostolic College alone, of which Peter is the head . . . that we believe the Lord entrusted all the benefits of the New Covenant in order to establish on earth the one Body of Christ, into which all those who already in some way belong to the people of God ought to be fully incorporated. (UR 3, emphases added)

The Decree also recalls that while there is a “hierarchy” of Catholic truths, insofar as these vary in “their relationship to the foundation of the Christian faith,” this does not mean that the less “fundamental” Catholic beliefs—those not shared by Protestant or Orthodox Christians—are “negotiable” or can be swept under the rug. (The revealed truths about our Lady, for instance, derive from the Incarnation, not vice versa.) On the contrary, “It is of course essential that [Catholic] doctrine be presented in its entirety. Nothing is so foreign to the spirit of ecumenism as a false irenicism which harms the purity of Catholic doctrine and obscures its genuine and certain meaning” (UR 11).

(2) Does UR imply a gradual descent into naturalism at the expense of divine revelation, leading to an abandonment of all revealed truth? No, because it never accepts the premise that Pius XI says leads to that “dead end,” namely, the modernist idea that the different religions all just “give expression, under various forms, to that innate sense which leads men to God.” The conciliar teaching, in contrast to this naturalistic account of religion, stresses the supernatural realities of revelation and faith. UR asserts that “the Catholic Church has been endowed with all divinely revealed truth and with all means of grace” (UR 4; cf. UR 3). Furthermore, “Christ entrusted to the College of the Twelve the task of teaching, ruling and sanctifying. . . . And after Peter’s confession of faith, he determined that upon him he would build his Church . . . [and] entrusted all his sheep to him to be confirmed in faith” (UR 2). The Fathers who promulgated UR were of course also those who, just one year later, promulgated the Dogmatic Constitution on Divine Revelation, which serves as an interpretative key to other conciliar documents touching on that subject.

(3) Does UR envisage a united “Church” of the future as being a “federation” of different Christian denominations agreeing to differ in at least some doctrinal matters? Nowhere is there any such suggestion. Vatican II presents the unity willed by God as one in which everyone is—surprise, surprise!—Catholic. Having made it clear that by “the Church” they mean the body led by “the bishops with Peter’s successor at their head”—i.e., the Roman Catholic Church—the Fathers continue:

The Church, then, God’s only flock, like a standard lifted high for the nations to see it, ministers the gospel of peace to all mankind, as it makes its pilgrim way in hope towards its goal, the fatherland above. This is the sacred mystery of the unity of the Church, in Christ and through Christ, with the Holy Spirit energizing its various functions. (UR 2, emphases added)

(4) From what has been said already, it should be clear that the Decree on Ecumenism does not teach the fourth heresy censured by Pius XI in Mortalium Animos, namely, the idea that Church unity is a mere future ideal which separated Christians must work to construct, insofar as it does not yet exist. Of course, we need to distinguish carefully here between the unity of the Church as such and unity among Christians. Obviously, if we understand the word “Christian” to cover everyone who professes faith in Christ, the latter unity does not exist yet—and never has existed since the first schisms arose in New Testament times! But such divisions do not imply that the Church herself is—or ever could be—disunited, in the sense of being divided into different denominations holding different doctrines. Our creedal article of belief in ” One, holy, Catholic, apostolic Church” rules this out. And so does UR when it expresses the hope that, as a result of ecumenism,

little by little as the obstacles to perfect ecclesiastical communion are overcome, all Christians will be gathered, in a common celebration of the Eucharist, into the unity of the one and only Church, which Christ bestowed on his Church from the beginning. This unity, we believe, exists completely (Lat., subsistit) in the Catholic Church as something she can never lose, and which we hope will continue to increase until the end of time. (UR 4, emphases added)

Whether or not, in the decades since Vatican II, ecumenism as UR expounds it has always been faithfully implemented—even by the Church’s own leadership—is of course a distinct question. A further one is whether or not the results achieved after about half a century vindicate, with the benefit of hindsight, the prudence of UR’s “window-opening” disciplinary changes. I think Catholics can now legitimately debate both these questions. In any case, if this brief comparison has helped to show that the Council did not fall into the doctrinal aberrations reprobated by Pius XI in 1928, it will hopefully have served a useful purpose.

[This article first appeared in the July-September 2008 issue of the Australian quarterly Oriens. Reprinted with permission.]


The “Subsists In” Controversy

In June 2007, the Congregation for the Doctrine of Faith released a statement, Commentary on the Document: Responses to Some Questions Regarding Certain Aspects of the Doctrine on the Church, which sought to clarify some of the Second Vatican Council’s teachings on authentic ecumenism. The CDF statement was met with some controversy because it stated that non-Catholic Christian “ecclesial communities” (with the exception of Orthodox traditions) could not be termed true “churches.” In saying this, however, the CDF was merely reiterating what Unitatis Redintegratio had already established:

Catholic ecumenism might seem, at first sight, somewhat paradoxical. The Second Vatican Council used the phrase ” subsistit in ” in order to try to harmonize two doctrinal affirmations: on the one hand, that despite all the divisions between Christians the Church of Christ continues to exist fully only in the Catholic Church, and on the other hand that numerous elements of sanctification and truth do exist without the visible boundaries of the Catholic Church whether in the particular churches or in the ecclesial communities that are not fully in communion with the Catholic Church. For this reason, the same Decree of Vatican II on ecumenism Unitatis Redintegratio introduced the term fullness ( unitatis/catholicitatis) specifically to help better understand this somewhat paradoxical situation. Although the Catholic Church has the fullness of the means of salvation, nevertheless, the divisions among Christians prevent the Church from effecting the fullness of catholicity proper to her in those of her children who, though joined to her by baptism, are yet separated from full communion with her. The fullness of the Catholic Church, therefore, already exists, but still has to grow in the brethren who are not yet in full communion with it and also in its own members who are sinners until it happily arrives at the fullness of eternal glory in the heavenly Jerusalem. This progress in fullness is rooted in the ongoing process of dynamic union with Christ: Union with Christ is also union with all those to whom he gives himself. I cannot possess Christ just for myself; I can belong to him only in union with all those who have become, or will become, his own. Communion draws me out of myself towards him, and thus also towards unity with all Christians. ( Commentary on the Document: Responses to Some Questions)

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