KIM LAWTON: They have a common origin, tracing their roots to Jesus and his disciples. They share a belief in the Trinity, God as Father, Son, and Holy Spirit. And they have many similar sacraments. But their 1,000-year-old schism has been one of the bitterest divides in Christianity.

FATHER RON ROBERSON (National Conference of Catholic Bishops): You know, there was really very little sense of commonality, of communication between the two sides, and so you just had this kind of cold, icy silence that went on for a very, very long time -- for a period of centuries, in fact.

LAWTON: International delegates from both traditions are in Emmitsburg, Maryland, trying to negotiate more of a thaw. The closed-door meetings are reigniting an effort at international dialogue that began 20 years ago but has been stalled for the last seven years.

ARCHBISHOP STYLIANOS (Representative, Ecumenical Patriarchate): This dialogue between the Orthodox Church and the Roman Catholic Church is the most distinguished because it is the most difficult.

LAWTON: The most difficult because the tensions stretch back to the earliest days of Christianity. As the new faith became the official religion of the Holy Roman Empire, questions of doctrine and administration were addressed by councils of Church leaders from across the empire. But by the turn of the fifth century, the Roman Empire was politically divided into the Latin-speaking western empire, centered in Rome, and the Greek-speaking Byzantine empire of the East. Those political divisions put tremendous pressure on the Church.

PROFESSOR RANDALL MORRIS (William Jewell College): Between political divisions, language barriers, indeed, developing of traditions in isolation from one another, this just ended up magnifying the differences that at first were not significant, but in the end grew very large.

LAWTON: There were also crucial theological issues, such as the differing understandings of how the Holy Spirit fits into the Trinity and ecclesiastical authority.

In the East, the Church took on a more decentralized character, which continues today, with regional churches led by bishops of equal standing. The powerful bishop of Constantinople, the Ecumenical patriarch, was simply the first among equals.

In the West, there was a more centralized structure, headed by the bishop of Rome, the pope, who claimed Churchwide authority.

FATHER ROBERSON: The East has always been uneasy about the way the papacy has functioned within the Church, even back in the early centuries before the schism between East and West.

LAWTON: That formal split between the churches, known as the Great Schism, came in 1054. It was cemented with the Crusades, when western Crusaders attacked eastern Christians and sacked Constantinople during their efforts to recapture the Holy Land from the Muslims. A virtually complete chasm between the two churches continued until the 1960s, when the first overtures of peace began, overtures that led to a new openness for discussions.

Bridging 1,000 years of division isn't easy. This is only the eighth time this group has met since the dialogue was launched in 1979. The last meeting was seven years ago, when the talks ended in stalemate. This session was postponed three times, most recently last year because of tensions over NATO bombing in Serbia.

PROFESSOR MORRIS: There is going to be very strong feelings on both sides. These are feelings that have to be aired. They have to be addressed. And so it wouldn't surprise me if there were very heated discussions behind closed doors.

LAWTON: The specific topic on this meeting's agenda is another tension-filled by politics -- in this case, the fall of communism. The reemergence of religious freedom in Eastern Europe has resurrected centuries-old animosities between the Orthodox and eastern-right Catholics. Eastern-right Catholics maintain many Orthodox liturgical practices, but are affiliated with Rome. They want the return of property seized by the communists and given to the Orthodox. The Orthodox, meanwhile, resent missionaries who converted Orthodox believers to Catholicism.

ARCHBISHOP STYLIANOS: Christians on both sides know that this is the most thorny problem.

LAWTON: Observers say resolution of this will pave the way for new dialogue on theological differences, such as the very tough issue of the primacy of the pope.

MATTHEWES-GREEN (Holy Cross Antiochian Orthodox Church): His role in the church is a major question that has to be dealt with in these conversations. Now they won't -- they won't talk about it at this particular dialogue, but sooner or later it's the big question that'll have to be faced.

LAWTON: Ironically, Pope John Paul II has been one of the strongest supporters of this dialogue. He has said one of the greatest regrets of his papacy is being unable to foster reconciliation with the Orthodox. Earlier this year, he hosted a special service at the Vatican, where Catholic, Orthodox, and Anglican leaders sought forgiveness for the lack of Christian unity among their churches, something Jesus commanded of his followers.

The goal of this dialogue is full communion between Orthodox and Catholic churches. Both sides agree that is not likely to happen anytime soon.

FATHER ROBERSON: I think it's realistic that you have to take a long-term view of the situation. Remember, once again, the division between East and West took place over a very long period of time, a period of centuries, and that kind of division isn't going to be resolved over a couple of decades.

FATHER MATTHEWES-GREEN: It would depend on the sort of time line, I think, that you put on it. I personally can't imagine it within my lifetime.

LAWTON: Still, leaders of the dialogue say this meeting is an important step in the process.

CARDINAL WILLIAM KEELER (Archdiocese of Baltimore): Every time we come together, we have an opportunity to get to know each other a little bit better. It'll help to see how faith is taught and lived and how important it is in the lives of both our churches.

LAWTON: This prayer service may be symbolic of the complexities ahead. Originally, it was scheduled as a joint service to be led by representatives of both traditions, but the two sides couldn't agree on the details. In the end, it was a Catholic service with Orthodox leaders sitting in the front rows. Together, they prayed for God's guidance in their quest for reconciliation. People here say that's the only way true unity will be achieved. I'm Kim Lawton in Emmitsburg, Maryland.

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