In terms of budget, personnel, and global reach, the Roman Catholic Church rivals the United Nations, and as far as having a track record of promoting tolerance and peace without resorting to force, it has no equal among states. Over Christianity’s 2,000-year history, its message of love, charity, and self-sacrifice has kept the religion popular and influential, even in the face of relentless attacks. The Soviet Union, for example, shut down churches and waged an aggressive antireligion campaign, but Christianity has outlasted communism. 

Christianity is mending a number of internal, long-standing ruptures as well. In the eleventh century, the faith splintered into the Western Catholic Church and the Eastern Orthodox Church. The sixteenth-century Protestant Reformation further damaged Christian unity. Today, however, global Christianity is poised to heal these rifts and emerge stronger than ever.

This project was made possible by Pope Benedict XVI, who retired in February, and will now be carried out by his successor, Pope Francis. When Cardinal Joseph Ratzinger became Pope Benedict in 2005, few expected him to accomplish much in the way of outreach and bridge building. In his previous position as the designated protector of church doctrine, Ratzinger had proved himself to be a strict traditionalist; in the run-up to his selection as pope, The Washington Post described him as “the guardian of orthodoxy.”

Yet Benedict’s authority as a renowned theologian and the happenstance of his German birth made him an unusually successful advocate for Christian unity. Indeed, Benedict did more during his eight-year reign to overcome the Great Schism of 1054 and the Protestant Reformation, and to promote interfaith dialogue, than any of his predecessors, including Pope John Paul II. In the process, he helped distinguish the Vatican’s worldview from Washington’s in important ways and paved the way for improved cooperation among Christians of various denominations on religious, moral, and political issues worldwide. Francis will undoubtedly continue this effort. In his native Argentina, he championed interfaith cooperation and dialogue.


Christianity is divided into three main groups: Roman Catholics, who number 1.2 billion and constitute approximately 50 percent of all Christians worldwide; Protestants, who are divided into thousands of denominations and together number 801 million, or 37 percent of the global total; and Orthodox Christians, who make up 12 percent of Christians with their 260 million adherents (approximately 39 percent of whom live in Russia). According to the Pew Forum on Religion and Public Life, Catholicism is growing fastest in Asia and Africa. Protestantism is also spreading globally: of the countries with the top ten Protestant populations, only two are in North America or Europe.

As these churches have grown in recent years, they have also grown closer together. Ecumenism -- the movement to unify Christianity -- is on the rise, partly in response to secularization, which tends to marginalize Christianity’s relevance, and partly in response to a recent escalation in violence against Christians around the world. A shared sense of vulnerability has drawn Christians closer together, but it took Benedict’s push to institutionalize this effort in ways that will continue long after the end of his tenure.

Benedict began his pontificate with a strong existing foundation for pursuing ecumenism. The Second Vatican Council, a three-year assembly convened in the early 1960s, fundamentally changed how the church did business and made broad Christian unity possible. One of the council’s key documents, Unitatis Redintegratio (Restoration of Unity), issued in 1964, identified “restoration of unity among all Christians” as a key long-term goal. The document described baptized Christians who profess faith in another church as “separated brethren,” not as “heretics,” the term commonly used for centuries prior. And in 1964, the Roman Catholic Church and the Eastern Orthodox Church canceled their mutual excommunications of one another (dating back to 1054), thereby allowing interchurch dialogue to begin.

John Paul II furthered these efforts over the course of his papacy. He made specific inroads with several Protestant denominations, allowing former Episcopal priests to become Catholic priests and accepting some Episcopal parishes into the Catholic Church, as well as signing a joint declaration with the Lutheran World Federation that resolved a key doctrinal difference over what is known as “justification” -- how a sinner gets to heaven. John Paul II was also the first pope to visit a majority Orthodox country: Romania, in 1999. Later, he also traveled to the Orthodox countries of Bulgaria, Georgia, Greece, and Ukraine. Still, he was never able to achieve his dream of meeting with Alexy II, then the Russian patriarch and one of the most powerful figures in the Eastern Orthodox Church.

That failure was due in part to the Cold War, when the Soviet Union treated the Polish pope as an anticommunist agitator. But even after the collapse of communism, palpable tensions kept Catholics and Orthodox Christians apart. These disputes included Catholic property claims against the Russian state, which had expropriated, repurposed, or destroyed thousands of churches, monasteries, and ecclesiastic buildings during the Soviet era; Orthodox fears that Catholics and other missionary churches would sweep into Russia to woo believers; centuries of Polish-Russian rivalry; and missteps by the Vatican in how it structured new Catholic administrative units in Russia in the early 1990s.

Relations between the Catholic Church and the Russian Orthodox Church reached a low point in 2002, when Moscow prevented Jerzy Mazur, a bishop who had been rebuilding Catholicism in Siberia, from returning to Russia from his native Poland and kicked out or banned several other Catholic priests. The Vatican’s top administrator for European Russia, Archbishop Tadeusz Kondrusiewicz, complained that “an organized campaign is being waged against the Catholic Church in Russia.”


The feud began to ease with Benedict’s ascension in April 2005. In his first papal message to his former peers, assembled in the Sistine Chapel, Benedict (speaking in the third person) set forth a clear platform of Christian reconciliation: “The current Successor assumes as his primary commitment that of working tirelessly towards the reconstitution of the full and visible unity of all Christ’s followers. This is his ambition, this is his compelling duty. He is aware that to do so, expressions of good feelings are not enough.”

Benedict began his outreach almost immediately. On his first papal trip, to Germany four months later, Benedict met with an assembly of German evangelicals and Protestants and told them that ecumenism “does not mean uniformity in all expressions of theology and spirituality, in liturgical forms and in discipline.” He declared, “Unity in multiplicity, and multiplicity in unity.” The pope ended his talk with a call for collaboration: “Now let us all go along this path in the awareness that walking together is a form of unity.” He also pledged to promote interfaith dialogue by stressing the unifying word of God and collaborating across faiths on issues such as the defense of life and the promotion of peace.

Benedict soon inadvertently compromised his own plan to promote further dialogue, however. The next year, in a speech at the University of Regensburg, in Germany, Benedict quoted a fourteenth-century Byzantine emperor disparaging the founder of Islam: “Show me just what Mohammed brought that was new and there you will find things only evil and inhuman, such as his command to spread by the sword the faith he preached.” The pope had quoted the emperor only in order to reflect on the question of whether acting unreasonably -- for example, by forcing conversions through violence -- was against God’s nature. Benedict also took care to reject the “startling brusqueness” of the emperor’s remark, calling it “unacceptable.” But his citation was taken out of context and ignited protests throughout the Muslim world. The Vatican responded by conveying the pope’s “sincere regret,” but the rioting spread, leading to the bombing of churches in the West Bank and Gaza and the murder of a 65-year-old nun in Mogadishu, Somalia.

The speech also unnerved the Vatican by unintentionally yoking the pope to negative perceptions of U.S. President George W. Bush’s foreign policy that were prevalent in the Muslim world, where many people interpreted the pope’s comments as an endorsement of a “war on Islam” led by the United States. In fact, Vatican diplomats had emphatically objected to one of the most significant elements of the “war on terror”: the invasion of Iraq. John Paul II had even sent a personal envoy to discourage Bush from attacking Iraq. But the Regensburg speech made Benedict look like the champion of a strategy the Vatican strongly disapproved of, and it endangered the people and communities the pope most wanted to protect.


In an attempt to make up lost ground, the Vatican reconfigured Benedict’s first papal visit to a majority Muslim country, Turkey, in November 2006. The initial purpose was to join Bartholomew I, the archbishop of Constantinople and the spiritual leader of the Eastern Orthodox Church, for the Feast of Saint Andrew. Many advisers counseled Benedict to cancel the trip because it was bound to spark more Muslim protests. Two days before the pope arrived, an estimated 25,000 people demonstrated against his visit in the streets of Istanbul.

But Benedict quelled the noise by showing, for the first time in his papacy, the same deft touch that his predecessor had possessed in abundance. He did this by visiting Istanbul’s Sultan Ahmed Mosque, making him just the second pope in history to enter a Muslim holy place. Accompanied by Mustafa Cagrici, the mufti of Istanbul, and Emrullah Hatipoglu, the mosque’s imam, Benedict removed his bright red loafers on entering as a sign of deference. Then, he stood next to Cagrici, facing Mecca, and recited a prayer -- and in so doing managed to stanch Muslim fury through his show of respect.

These were meaningful gestures in the eyes of Muslim leaders. As a result, for example, a year later, King Abdullah of Saudi Arabia-, the protector of Mecca, visited Rome, becoming the first Saudi monarch to visit a pope. (With about one million Catholics living in the kingdom, mostly guest workers from the Philippines with limited rights to practice their faith, the Vatican’s interest in this relationship is practical.) And the pope was invited to Jordan and the Palestinian territories in 2009 and to Lebanon last September, which ended up being his last papal trip.

In Turkey, Benedict went on to meet with Bartholomew under tight security. In a prayer service at the modest Church of Saint George, Bartholomew greeted the pontiff as a “beloved brother,” and Benedict responded by quoting the 133rd psalm: “Behold, how good and pleasant it is when brothers dwell in unity.” The two spoke at length about the ecumenical mission and the promotion of peace through love. They prayed together before relics of Saint John Chrysostom and Saint Gregory of Nazianzus, former bishops revered by both churches. The relics had been taken to Rome in 1204 after Constantinople was captured during the Fourth Crusade. Five months before his death, John Paul II had sent them back to the patriarchate of Constantinople.

The visit culminated with Benedict and Bartholomew releasing a common statement and appearing together at the patriarch’s residence in Istanbul, clasped hands held aloft. They also expressed “profound joy” that a Catholic-Orthodox theological commission, comprised of 30 experts from each faith, had overcome internal divisions and reconvened after a six-year hiatus to systematically narrow the doctrinal differences standing between the two churches.

Bartholomew presides over a tiny Orthodox community in Istanbul, increasingly hemmed in by the re-Islamization of Turkey. During his visit, Benedict demonstrated how Muslim hostility can be dealt with by supporting local Christian communities that have historically served as bridges between the East and the West. Bartholomew visited Rome several times after that, mending the Great Schism a little more with each visit. In June 2008, the patriarch participated in a Mass in Saint Peter’s Basilica with the pope, during which the two men recited the Nicene Creed together in Greek, leaving out a three-word phrase (“and the son”) that the Orthodox do not accept. With this deft bit of statecraft, Benedict overcame -- or at least sidestepped- -- a significant doctrinal disagreement that had prevented cooperation between the churches for centuries.


The biggest development in deepening East-West dialogue, however, came in January 2009, with the ascension of a new Russian Orthodox patriarch, Metropolitan Kirill. Kirill had served for 20 years as chair of the Russian Orthodox Church’s Department for External Church Relations, a role that essentially made him the church’s foreign minister. In that position, he was the Vatican’s main interlocutor in the postcommunist era and had already established a working relationship with Benedict by the time he became patriarch. For both John Paul II and Benedict, according to Vatican insiders, Kirill’s Orthodox clerical lineage contributed to their trust: his grandfather was a persecuted priest, arrested by the Soviets in 1933; his father was a priest; and his brother is an archpriest and theology professor.

Kirill and Benedict share a belief that the survival of Western culture depends on its historic Christian values of virtue and freedom, making them natural allies. For these men, both of whom lived through totalitarian oppression, rampant secularism is a harbinger of the kind of moral collapse that can lead to instability and even tyranny. They are also both wary of radical Islam and its threat to minority Christian populations around the world.

Today, Kirill can advance his ideas from a position of strength: the Russian Orthodox Church is growing and is closely allied with the Russian government, giving the church muscle and relevance. Between 1987 and 2009, the number of monasteries in Russia grew from three to 478, the number of seminaries increased from two to 25, and the number of churches skyrocketed by 550 percent, from 2,000 to 13,000.

Political relations between the Russian Orthodox Church and Vatican City improved greatly during Benedict’s tenure. In 2010, for the first time since the 1917 Bolshevik Revolution, Russia and the Vatican exchanged ambassadors based on full diplomatic recognition. Benedict’s outreach to Russia helped mend the centuries-long Polish-Russian divide, which in part explains the cold shoulder Moscow usually gave John Paul II. In the summer of 2012, the Roman Catholic bishops of Poland and the Russian Orthodox patriarch joined together in Poland to urge Poles and Russians to overcome their “mutual prejudice.” It was the first time a Russian patriarch had ever visited modern Poland, and the event was broadcast live on Polish television.

The growing warmth between the Catholic and Orthodox churches helped pave the way for these positive developments, but so did respectful relations between Russian President Vladimir Putin and Benedict. The two men first met in March 2007 at the Vatican, where they conversed in the pontiff’s native German. During the visit, according to a U.S. State Department cable released by the whistleblower website WikiLeaks, Putin, who is a practicing Orthodox Christian, pledged that his government would “do all it can to favor dialogue between the two churches.” The Vatican sees Russia, together with Europe and Latin America, as part of Western civilization -- which is different from Washington’s view.

Good relations between Catholic and Russian Orthodox leaders will likely continue. Metropolitan Hilarion, the 46-year-old priest and composer who replaced Kirill as the church’s leader for external relations, is a young star with an impressive resumé, a familiar face in Rome who is also comfortable in the United States and throughout Europe, and a determined advocate of ecumenism. He advocates the importance of the Catholic and Orthodox churches’ coordinating their answers on moral questions and waging a coordinated fight against Western “Christophobia.” In 2009, for example, the European Court of Human Rights declared that Italian public schools should remove all crucifixes from their classrooms because they are violations of the Europe Convention on Human Rights. The Roman Catholic, Russian Orthodox, and Greek Orthodox churches successfully worked together to reverse the ruling.

More recently, when the Russian government was coming under intense international fire for jailing three members of the punk band Pussy Riot for initiating a guerrilla-style political protest on the alter of a historical Moscow cathedral, Catholic and Protestant entities sent letters of support to the Russian Orthodox Church. As the Catholic Church’s Council of European Bishops’ Conferences explained, they “reject the tendency to misunderstand freedom of art and freedom of expression when there is in fact instigation . . . for provocative purposes in order to damage religious peace or to incite hatred against religion or religious presence in public life.”

In a congratulatory note to Francis, Kirill praised the positive relationship that developed between the two churches under Benedict. He emphasized the need to “join forces” to defend persecuted Christians and promote “traditional moral values in modern secular societies.” Francis is familiar with the Eastern Orthodox faith: in Argentina, he served as the chief church administrator for Eastern-rite Catholics, who follow the Orthodox liturgy while maintaining loyalty to Rome. Thus, the new pope is already attuned to the history and nuances of the Orthodox faith.


In an unprecedented push for Christian unity, Benedict invited several special guests to a synod of bishops last October. Both Hilarion and Bartholomew were in attendance. And for the first time in history, such a synod featured an address by the spiritual leader of the Church of England. The archbishop of Canterbury, Rowan Williams, delivered an address on the importance of contemplation -- the meditative attitude that underlies prayer, religious art, and wisdom -- and the next day, he and Bartholomew joined the pope at a Mass celebrating the 50th anniversary of the Second Vatican Council.

Williams and Benedict have maintained a warm friendship ever since the pontiff’s 2010 trip to the United Kingdom to beatify an Anglican convert to Catholicism, Cardinal John Henry Newman. During this trip, Benedict became the first pope to enter Westminster Abbey, which had been a Catholic Benedictine abbey until King Henry VIII converted it into an Anglican cathedral after England’s split with Rome in the mid-sixteenth century. Henry VIII’s dispute with Catholicism centered on papal primacy; on most other matters, the king agreed with Catholic theology. As a result, there are few doctrinal differences between the Roman Catholic Church and the Church of England (known as the Episcopal Church in the United States), easing the task of reconciliation.

Indeed, relations between Catholics and Anglicans improved under Benedict’s leadership. In 2011, against the advice of British bishops, the pope created a unique canonical structure to receive groups of Anglicans into full communion with Rome. Benedict established three “personal ordinariates,” in the United Kingdom, the United States, and Australia, to accommodate clergy (including married priests, but not married bishops) and believers who want to convert to Catholicism while maintaining “liturgical, spiritual, and pastoral traditions.” Each ordinariate is led by a former Anglican priest who has executive authority over the community and reports directly to the pope. The Vatican says it crafted this policy in response to requests from hundreds of Anglicans around the world, including over 50 bishops, who expressed interest in joining the church without losing their traditions.

Given what he could have perceived as the Catholic Church’s theft of Anglican followers, it is remarkable that Williams not only maintained cordial relations with Benedict but also went out of his way to join him at religious services. Anglican leaders viewed Benedict’s actions not as poaching but as a means of preserving a common Christian identity. Reacting to the pope’s resignation, Justin Welby, who replaced Williams as the archbishop of Canterbury in early 2013, praised Benedict’s “great dignity, insight, and courage.” Francis, too, is respected by Anglican leaders. Gregory Venables, the former archbishop for the Anglican Church of the Southern Cone of America, recently described Francis as “much more of a Christian, Christ centered and Spirit filled, than a mere churchman. He is consistently humble and wise, outstandingly gifted yet a common man.”

Benedict made headway in reconciling with other Protestants as well. Broadly speaking, Protestantism, which began as a reaction to corruption in Rome, makes four main claims against Catholic theology. First, Protestants believe that salvation is obtained through faith in Jesus Christ, whereas Catholics hold that salvation is an ongoing event in which God’s grace creates faith and inspires good works. Second, Protestantism rejects the Catholic hierarchy of bishops led by a pope. Third, Protestantism holds that the Bible alone is enough to guide the faithful, whereas Catholics believe that church teachings and writings throughout history are also authoritative. Fourth, most Protestant denominations interpret the Eucharist as a symbolic representation of Christ’s sacrifice, whereas Catholics believe the Eucharist is the real presence of Christ.

Given these doctrinal differences, it was surprising when in 1999 the Pontifical Council for Promoting Christian Unity and the Lutheran World Federation (which represents 70.5 million Lutherans in 79 countries) signed a joint statement establishing “a common understanding of our justification by God’s grace through faith in Christ.” This phrase overcame almost 500 years of theological dispute and paved the way for a shared future. The statement also nullified past mutual condemnations. And in 2006, the World Methodist Council, representing 80 million people worldwide, voted unanimously to sign the agreement as well.

Christian unity will only grow stronger under Francis’ leadership. The ecumenical magazine Christianity Today has called Francis “a pope for all Christians,” and he is known for befriending, praying with, and studying the Bible with religious leaders of different faiths.


The search for common purpose among Catholics, Orthodox Christians, and Protestants has advanced not only thanks to Benedict’s efforts but also in reaction to broad global trends. In the developed world, where Christianity is threatened by secularization and materialism, the forces that unite the faithful -- namely, the core beliefs that Christ is Lord and Savior and that loving one’s neighbor is a spiritual requirement -- are more powerful than the somewhat obscure doctrinal differences that divide them.

Meanwhile, a disturbing global trend of violence against Christian churches and believers has led church groups to pressure governments and multilateral organizations to provide protection -- a campaign more effectively waged en masse. The Roman Catholic Church has diplomatic relations with 180 countries and maintains a permanent observer status in most un organizations. When defending a Christian who has been jailed for his or her beliefs -- as is happening with greater frequency, especially in Muslim-majority countries -- this diplomatic network offers Christians of all stripes a powerful resource. Furthermore, Catholic, Orthodox, and Protestant leaders outside the United States believe that U.S. foreign policy since 2003, with its heavy reliance on military intervention and minimal respect for local cultures and traditions, has disastrously jeopardized Christians and the cause of peaceful dialogue around the world.

Finally, traditional Christians, whose spiritual outlook is premised on the protection of human life, the family, heterosexual marriage, and the poor, have been united across sectarian lines for some time when it comes to political issues, such as abortion and gay marriage -- even when their churches have not formally collaborated. Not waiting around for formal doctrine to catch up, this Christian community is a strong force for ecumenical collaboration. It considers it urgent, not optional, to work together.

The pursuit of Christian unity will continue under Francis, not only because the new pope already has a good ecumenical track record but also because the threats of materialism, intolerance, and oppression show no signs of abating. In addition, institutional mechanisms for dialogue, such as the Pontifical Council for Promoting Christian Unity, have built up momentum that is unlikely to dissipate. And Francis is personally committed to Christian unity. For the past ten years, he has been an active leader of the Argentine ecumenical group Renewal Communion of Catholics and Evangelicals in the Holy Spirit.

Christian leaders of all denominations agree with near unanimity on the value of greater collaboration. Occasional local disputes still crop up; in Russia, some Orthodox clergy have been less than welcoming to Catholics and Protestants establishing new churches, and in parts of Latin America, Catholic bishops have expressed alarm over the rising popularity of Protestant denominations. But the leaders of the three main Christian groups favor good relations with one another and seek to spread that preference to their congregants.

Finally, Benedict’s last act as pope, his surprising decision to walk away from the job, should also contribute to the cause of Christian reconciliation by helping the Catholic Church rethink the nature of papal authority -- the very subject that has, to date, posed the greatest obstacle to Christian unity.

Francis’ behavior so far indicates a rethinking of the papacy. On the balcony of Saint Peter’s Basilica, immediately after his selection, he referred to himself as “bishop of Rome,” the most modest papal title. Francis dresses and travels unpretentiously and discouraged peers from spending money to attend his installation. All this reveals a plan to undercut the imperial trappings of the papacy -- a goal already respected by other Christian leaders. Francis will certainly uphold Catholic doctrine, but by making Jesus Christ and the gospel the central focus of his pontificate, he will enhance Christian unity as well.

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