This coming July 7th will mark the tenth anniversary of Benedict XVI's "motu proprio" Summorum Pontificum, a document that liberalized the use of the Roman liturgy as it celebrated prior to the reforms following the Second Vatican Council (1962-65).

This is one of Pope Benedict's acts that is destined to have a deep and long-term impact on the life of the Church.

The 2007 "motu proprio" addressed the concerns of certain groups of traditionalist Catholics that were very small, marginal and barely visible. Summorum Pontificum and Joseph Ratzinger changed their situation considerably.

To paraphrase one of Winston Churchill's wartime speeches, "Never was so much owed by so few to one pope".

Paul VI and John Paul II had already sought to accommodate liturgical traditionalists by issuing special indults for celebrating the pre-Vatican II liturgy, most particularly in 1984 and 1988. But they never cast any doubt on the legitimacy and the good fruits of the Vatican II liturgical reform, the theological and ecclesiological framework of which is found in the constitution Sacrosanctum Concilium.

Those earlier popes saw a fundamental coherence between the tradition of the Church, the theology of Vatican II and the council's liturgical reform.

But this picture changed significantly under Benedict XVI, whose pontificate needs to be analyzed in its complexity; that is, through his speeches, policy decisions, and personnel appointments. It makes no sense to interpret the theology of his entire pontificate solely on the basis of his address on the "two hermeneutics" of Vatican II or on his encyclicals.

There is little doubt that Benedict expressed and embodied a clear shift from a magisterium that saw Vatican II as part of the tradition of the Church to a magisterium that saw the tradition and Vatican II in much more complicated terms. Certain issues, such as the liturgical reform, were seen in tension and opposition.

While it is certainly too early to assess the long-term effects of Summorum Pontificum, it is necessary to begin the effort. For example, ten years on it is striking to re-read Benedict's hasty, and failed, attempt to stop the tendency to interpret the "motu proprio" as a denunciation of Vatican II, which – in fact – is widespread in Catholic traditionalist circles.

"In the first place, there is the fear that the document detracts from the authority of the Second Vatican Council, one of whose essential decisions – the liturgical reform – is being called into question," the former pope wrote in his letter accompanying Summorum Pontificum.

However, he then declared: "This fear is unfounded."

Moreover, Benedict expressed the wish that "the two forms of the usage of the Roman Rite can be mutually enriching".

But on both accounts, the reality of these last ten years has produced something very different from the former pope's stated intentions. In fact, the backlash against Vatican II has been a key component of the enthusiasm (and nostalgia) for his pontificate, while the coexistence of the two forms of the Roman rite within particular communities remains a chimera.

Yet there are two phenomena that are part of the post-Summorum Pontificum ecclesial and theological landscape of Roman Catholicism, which are difficult to separate from the pontificate of Benedict XVI.

The first phenomenon is that Summorum Pontificum boosted the pre-existing, sociologically limited world of liturgical traditionalism and projected it onto the wider world of the Catholic Church, especially among English-speakers. It is has given theological legitimacy to traditionalist views of the Vatican II liturgical reforms. And it has raised the visibility of traditionalist liturgy in the virtual spaces of the Catholic Church.

Over the past decade, social media has increasingly become a forum where the people of God can make their voices heard. Images of elaborate vestments used for pre-Vatican II liturgical celebrations have become part of the daily diet of those who follow the life of local churches and even prominent Church leaders.

This has had a significant impact on important parts of contemporary Roman Catholicism and its future – especially on committed Catholic youth and recent converts, as well as on seminarians and young priests.

The second phenomenon has been the reduction of Joseph Ratzinger's theology to that of traditionalism. In fact, Summorum Pontificum has helped to greatly distort the overall theological legacy of one of the most important theologians in the 20th century.

If Joseph Ratzinger's emphasis was on the tradition of the Church ("continuity and reform"), Benedict XVI's pontificate has been reduced, especially in these last few years, to an icon of traditionalism (against any kind of theological development, seen as "discontinuity").

This liturgical traditionalism has contributed to an overall traditionalist understanding of Catholicism to the point that it has become a problem and challenge for Pope Francis. Last year (July 11, 2016) the pope finally felt the need to intervene. In a statement released by the Holy See Press Office, he disavowed the so-called "reform of the liturgical reform", which Cardinal Robert Sarah – prefect of the Congregation for Divine Worship – had promoted a few days earlier during a public lecture to priests in London.

The Vatican statement warned that the notions of a reform of the reform "may at times give rise to error", but it also made clear that Francis did not intend to eradicate Catholic liturgical traditionalism. Rather, he wanted it to remain in the limited and specific place that his predecessor had assigned to it.

"The 'extraordinary' form, which was permitted by Pope Benedict XVI for the purposes and in the ways explained in his motu proprio Summorum Pontificum, must not take the place of the 'ordinary' one," the statement said.

So what are the lessons we've learned in the tens years since the publication of Summorum Pontificum?

First, there is a gap between the intended/declared and the unintended/undeclared goals of a papal act.

Second, there is sometimes a disconnect between the mind of Benedict XVI and how latter-day Ratzingerians have distorted his thinking (though not without the help of Ratzinger himself).

Third, there appears to be a link between liturgical traditionalism and the crisis of globalization and universalism within Catholicism.

Fourth, the resurgence of traditionalism is typical of all religions in the post-secular age.

And, fifth, liturgical traditionalism among Catholics has had a negative effect on the acceptance of other documents from Vatican II, such as those on ecumenism, inter-religious dialogue and missionary activity of the Church.

However, this is only a preliminary and very short list of the consequences of Summorum Pontificum.

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