Today, January 18, begins the International Week of Prayer for Christian Unity.

What do we pray for when we pray for Christian unity? What are the obstacles to unity that need to be overcome? 

When we think of obstacles to Christian unity, perhaps we think first of all of the important doctrinal differences separating Catholics, Orthodox and Protestants, from the papacy (which divides Catholics from all other Christians) to apostolic succession and the seven sacraments (which divides Protestants in various ways from Catholics and Orthodox), and of course the host of theological and practical questions dividing Protestants into their myriads of camps.

From this perspective, ecumenism at its best means building on what we have in common to try to overcome our differences on the points that divide us. At its worst, of course, ecumenism devolved into what Vatican II’s Decree on Ecumenism called “a false irenicism,” i.e., downplaying or dismissing doctrinal differences and promoting good manners and bomhomie rather than unity in Christ. 

The Catechism of the Catholic Church, in setting forth the Catholic understanding of “oneness” as one of the four marks of the Church, has this to say.

What are these bonds of unity? Above all, charity “binds everything together in perfect harmony.” But the unity of the pilgrim Church is also assured by visible bonds of communion:

• profession of one faith received from the Apostles;
• common celebration of divine worship, especially of the sacraments;
• apostolic succession through the sacrament of Holy Orders, maintaining the fraternal concord of God’s family. (Catechism of the Catholic Church, 815)

Encapsulated in those three bullet points are the substance of the issues over which Christians are divided and around which ecumenical discussion revolves.

Not so fast, though. Before the bullet points comes this important statement:

“Above all, charity ‘binds everything together in perfect harmony.’”

It’s easy to gloss over this because it’s uncontroversial. Obviously we all agree on that! That’s not what divides us. 

On the other hand, it’s important to recognize that the ultimate root of divisions between Christians is not different theological opinions, conclusions or beliefs. The ultimate root of divisions between Christians is sin — and sin, alas, is a nonsectarian reality. As the Decree on Ecumenism notes:

Even in the beginnings of this one and only Church of God there arose certain rifts, which the Apostle strongly condemned. But in subsequent centuries much more serious dissensions made their appearance and quite large communities came to be separated from full communion with the Catholic Church — for which, often enough, men of both sides were to blame.

That final admission is important because it highlights an important truth. As Catholics we believe we have a fullness of truth that non-Catholic Christians lack. That doesn’t mean, though, that we can sit back, complacent in our rightness, and wait for the Holy Spirit to convict non-Catholic Christians of their need to submit to the Pope. Nor can we put our faith in apologetical arguments to show why we’re right and others are wrong.

We must recognize that the sad story of division among Christians is a story of pride, partisan spirit, tribalism, triumphalism, wrath, unforgiveness, complacency and failure of love for God and neighbor. Such failings pave the way for sharpening of differences, breakdowns in understanding, mounting hostilities, and ultimately to anathemas, schisms and excommunications. 

I’m not saying anathemas and excommunications aren’t ultimately theologically warranted (on at least one side). I’m saying the road to anathema and excommunication is paved with the skulls of sinners on all sides. And, therefore, that the way forward is not simply a way of better or more sophisticated theological arguments, but of humility, repentance, faith and charity — again, on all sides. As Pope John Paul II writes in Ut Unum Sint: 

The Catholic Church acknowledges and confesses the weaknesses of her members, conscious that their sins are so many betrayals of and obstacles to the accomplishment of the Saviour's plan. Because she feels herself constantly called to be renewed in the spirit of the Gospel, she does not cease to do penance. At the same time, she acknowledges and exalts still more the power of the Lord, who fills her with the gift of holiness, leads her forward, and conforms her to his Passion and Resurrection.

Most Christians who are serious about their faith recognize that being united in love is not enough, that something else is necessary. A confessional Protestant might say “It’s not enough to be united in love; we must also be united in faith, defined by the correct interpretation of the Bible.” An Orthodox Christian might say “We must be united in adherence to the Tradition of the undivided Church.” A Catholic might say “We must be united in communion with the bishop of Rome, the successor to St. Peter.”

These are, indeed, the topics around which ecumenical discussion must turn. The problem comes when (for example) Catholics go on to think that because we as Catholics are united in communion with the bishop of Rome, we Catholics (at least non-dissenting, orthodox Catholics united in full communion of faith with the bishop of Rome) already have the unity Christ wants us to have.

We cannot afford to forget that if we are not also united in charity, our unity is flawed and diminished — still important, but not the fullness of unity Christ wishes for us.

It is not first of all by our theological orthodoxy, our visible communion with the bishop of Rome, our polemics against doctrinal error, our mastery of biblical arguments, or our hatred of heresy that our Lord said all men would know we are his disciples, but by our love.

That this is uncontroversial does not make it unimportant or pabulum — particularly when in practice the qualities for which we are known, not only by our non-Christian neighbors but also by our separated brethren and often enough even by our fellow religionists — are too often very far from love.

Am I saying that if we loved one another, doctrinal and ecclesiological differences would cease to matter? Of course not. What I’m saying is that we cannot say we have done all we can to overcome our differences and restore unity if we fail in love. The way forward in ecumenism does not begin with better or more persuasive theological arguments, but with love and humility and a willingness to cross-examine ourselves as well as our brethren.

Sometimes it may seem that when it comes to longstanding theological divisions, there’s nothing left to say and nothing to be done but for one side or the other to give in. But is this always the case? Consider the case of the Chalcedonian schism. 

Prior to modern times it was perfectly clear both to Rome and to the Orthodox Churches that the non-Chalcedonian Oriental Orthodox Churches were in heresy, denying the dual natures of Christ; it may have been equally clear to the Oriental Churches that Rome and the Orthodox wrongly divided the undivided Christ in two, after the fashion of Nestorius. After attempts at rapprochement at the Council of Florence failed, it must have seemed hopeless.

By the 20th century, though, the Christological issues began to look less unresolvable. Beginning with papal meetings with the heads of the Oriental Churches, an ecumenical dialogue was taken up, and gradually it became clear that we were divided less by differing fundamental beliefs than differences of expression. In 1984 Pope John Paul II and the Syriac Patriarch signed a joint declaration affirming that

The confusions and schisms that occurred between their Churches in the later centuries, they realize today, in no way affect or touch the substance of their faith, since these arose only because of differences in terminology and culture and in the various formulae adopted by different theological schools to express the same matter. Accordingly, we find today no real basis for the sad divisions and schisms that subsequently arose between us concerning the doctrine of Incarnation. In words and life we confess the true doctrine concerning Christ our Lord, notwithstanding the differences in interpretation of such a doctrine which arose at the time of the Council of Chalcedon.

Catholic vocabulary furnishes a helpful term for this kind of theological progress: We call it “doctrinal development.” The Eastern Orthodox reject this label — but similar conclusions regarding the substantial unity of faith have been reached in dialogues between Eastern Orthodox and the Oriental Churches.

Then there is the Filioque, a bone of contention that was far more divisive at the Council of Florence than the Petrine primacy. (Catholic and Orthodox participants at the Council debated the papacy for less than two weeks, but the Filioque for eight months!) Many Orthodox consider the Filioque a theological casus belli separating heresy from orthodoxy. As Bishop Kallistos Ware wrote in the first edition of The Orthodox Church,

Orthodox believe the filioque to be theologically untrue. They hold that the Spirit proceeds from the Father alone, and consider it a heresy to say that He proceeds from the Son as well.

But this point of view, too, has been changing over time—and Ware himself bears witness. The passage above is significantly revised in the second edition of The Orthodox Church, and in 1995 Ware explained why in careful language:

The filioque controversy which has separated us for so many centuries is more than a mere technicality, but it is not insoluble. Qualifying the firm position taken when I wrote The Orthodox Church twenty years ago, I now believe, after further study, that the problem is more in the area of semantics and different emphases than in any basic doctrinal differences.

It may seem incredible to suggest that the doctrine of the papacy could be similarly resolved. I suggest that we hope for too little because we love too little. On the Orthodox side, it is slowly becoming possible to acknowledge, for instance, that Peter himself is the rock on which Jesus builds his church in Matthew 16. On the Catholic side, we recognize today that the dogmatic definitions on the papacy of Vatican I are in need of further development and clarification, in part because Vatican I was suspended while its work was incomplete due to the capture of Rome by the Kingdom of Italy in 1870, and partly because of the new insights of ongoing theological and ecumenical work.

My journey to Catholicism took me through a great many varieties of Protestantism and led me to seriously consider Orthodoxy before becoming Catholic. These experiences, combined with my graduate studies in church history and theology in two Catholic seminaries and some three decades of ecumenical and apologetical dialogue, have left me with an unshakable conviction that Christian communities are divided because we don’t make unity a priority.

At the very least, I submit that the work of unity does not begin with arguments. It begins by embracing one another.

Particularly in this International Week of Prayer for Christian Unity, let us pray to love one another.