The centenary of the birth of Pope St. John Paul II on May 18 is not the only anniversary of note connected with him this month. On May 25, the Church marks the 25th anniversary of his landmark encyclical on Church unity entitled Ut Unum Sint, taken from Jesus’ prayer to the Father on Holy Thursday, “May they all be one” (John 17:11, 21).

This encyclical was the most courageous papal ecumenical proposal since the schism with the Orthodox in 1054 and the Protestant Reformation in 1517. It confirmed as “irreversible” the Second Vatican Council’s commitment in favor of Church unity and called all Catholics, as well as our brothers in sisters in other churches and ecclesial communities, to renew and increase their efforts to respond to Christ’s appeal to work for full and visible communion.

“The way of ecumenism,” John Paul II stated, “is the way of the Church.”

It has to be the way of the Church because unity is, first, an indispensable mark of the Church. The Church was founded as the Mystical Body of Christ and is meant to reflect the communion that exists among the Persons of the Blessed Trinity, providing an earthly image of the communion of saints in heaven.

St. Paul emphasized this among the members of the early Church, reminding them, “You are all one in Christ Jesus,” and “There is one body and one Spirit, just as you were called to the one hope of your calling, one Lord, one faith, one baptism” (Galatians 3:28; Ephesians 4:1-6). Church unity is not something we create by our own efforts and negotiations, but is a reality God himself has created that the Church must once again evince.

When Jesus begged the Father that his disciples be one just as he and the Father are one, he declared that this would help the world “know that you sent me, and that you loved them even as you loved me” (John 17:23). The effectiveness of the work of evangelization, he implied, was contingent on the manifestation of the unity of believers. Lack of unity, as Vatican II regretted in Unitatis Redintegratio, its decree on ecumenism, “openly contradicts the will of Christ, scandalizes the world, and damages the holy cause of preaching the Gospel.” Pope St. Paul VI added, in Evangelii Nuntiandi, “We must offer Christ’s faithful not the image of people divided and separated by unedifying quarrels. … The division among Christians is a serious reality that impedes the very work of Christ.”

That’s why in Ut Unum Sint John Paul II stressed the centrality and urgency of the ecumenical task. He called ecumenism “one of the pastoral priorities of my pontificate” and said it “is not just some sort of ‘appendix’ that is added to the Church’s traditional activity. Rather, ecumenism is an organic part of her life and work, and consequently must pervade all that she is and does.” He stated simply, “To believe in Christ means to desire unity; to desire unity means to desire the Church; to desire the Church means to desire the communion of grace that corresponds to the Father’s plan from all eternity. Such is the meaning of Christ’s prayer: ‘Ut unum sint.’”

The ecumenical goal, he stated, cannot be achieved by “human powers and capacities,” and therefore the first step of ecumenism is public and private prayer for God’s assistance, opening ourselves to the work of the Holy Spirit, joining ourselves to Christ’s intentions and interceding for each other, that we may grow in ardent fidelity to God’s will.

The second step is conversion, a true change of heart, involving repentance and reparation for sins against unity, like “long-standing misgivings inherited from the past,” “mutual misunderstandings, prejudices, complacency, insufficient knowledge of the other,” “refusals to forgive” and “pride.” Conversion also involves striving to grow in “love, self-denial, humility, patience” and “renewal and reform of the Church.”

The third step is dialogue, which he says is not “simply an exchange of ideas … [but] always an exchange of gifts,” in which people enter as partners, all seeking reconciliation and unity and truth. Such dialogue, he adds, cannot take place just on the “horizontal dimension” of meetings and exchanges of points of view, but must feature a “primarily vertical thrust” in which we all seek, contritely, to listen to and respond to God. That perspective allows dialogue to take place in a context of love directed to God and in God toward others, as well as helps all partners remain faithful to what they consider essentials and to avoid false irenicism, indifference, half-hearted commitment, defeatism or prejudicial opposition. The most effective dialogue of all, he says, is that of the saints and the martyrs who witness to the will of God in things little and big until the end.

The goal of the ecumenical movement, he says, must be “nothing less than full communion between East and West,” so that the Church may “breathe with her two lungs.” The image he proposes is the way that different Churches related to each other in the first millennium of Christianity, in which there was unity with diversity.

He acknowledges that one of the major obstacles to unity is the understanding of the papacy. In the boldest part of the encyclical, he invites other Christians to a “patient and fraternal dialogue” about how the ministry of the Bishop of Rome, without renouncing anything essential, can reemerge as a “servant of unity,” “presiding in truth and love,” “done in communion” with the Churches and the bishops.

In the past quarter century, there has been much ecumenical progress. The Catholic Church continues high-level dialogue with 15 churches or associations of churches, and there have been notable breakthroughs: several agreements with ancient Churches of the East resolving the Christological controversies of the fifth century, an agreement on justification with the Lutherans in 1998, and common declarations on various points of faith and witness with the Greek Orthodox patriarch of Constantinople, the Russian Orthodox patriarch of Moscow and the Anglican archbishop of Canterbury.

The popes have welcomed many Christian religious leaders to Rome and met with them in their own residences and houses of worship on foreign trips, notably various Orthodox patriarchs, as well as Lutherans for the 500th solemn anniversary of the Protestant Reformation and the World Council of Churches on its 70th anniversary. There has been much common effort for peace, for the protection of our common home and for refugees and migrants, as well as in defense of Christians, who are being massacred in the Middle East and elsewhere. There have also been gestures of charity, involving the ecumenism of the saints, most notably Pope St. John Paul’s giving the Russian Orthodox the icon of Our Lady of Kazan, his returning the relics of St. John Chrysostom and St. Gregory of Nazianzen to Constantinople, and Pope Francis’ giving even some of the relics of St. Peter to Greek Orthodox Patriarch Bartholomew.

Astride these positive steps, there have been setbacks and disappointments. Some of the churches dating from the Reformation have separated themselves further from the common interpretation of the Church on the inspiration and inerrancy of sacred Scripture, the sacrament of holy orders, the meaning of marriage, and various aspects of sexual morality. There has also been a major split between the Orthodox patriarchates of Constantinople and Moscow over the Orthodox Church in the Ukraine.

Twenty-five years later, the momentum given by Ut Unum Sint remains, and the questions he asked with regard to the exercise of the papacy in Christianity as a whole are getting attention. Most of the progress has happened at the level of expert dialogue, not so much at the grassroots level — but clergy in various Churches are now receiving much more formation in ecumenism than before, giving them the capacity to bring a fraternal spirit to their houses of worship.

One last sign of hope is that one more saint in heaven, the author of Ut Unum Sint, who now, along with martyrs and saints from East and West, is able to intercede and work for the manifestation of the unity for which Christ prayed from the place where the full communion of believers within the communion of God shines in all its radiance.

Father Roger Landry is a

priest of the Diocese of

Fall River, Massachusetts,

and a papally appointed “missionary of mercy.”