Vatican City: This year marks the 30th anniversary of Ut unum sint (UUS), the groundbreaking encyclical on ecumenism issued by Pope St. John Paul II on May 25, 1995, coinciding with the Solemnity of the Ascension of the Lord. The document remains a foundational statement reaffirming the Catholic Church’s unwavering commitment to Christian unity.
Deacon Daniel Galadza, a professor at the Pontifical Oriental Institute in Rome and a member of the Ukrainian Greek Catholic Church, reflected on the enduring significance of Ut unum sint, especially in relation to the Eastern Churches. He emphasized that the encyclical builds directly upon the Second Vatican Council’s decree Unitatis redintegratio, formally confirming the Catholic Church’s resolve to engage in ecumenical dialogue and reconciliation.
A particularly notable aspect of Ut unum sint highlighted by Deacon Galadza is the terminology it uses for the Eastern Christian communities not in communion with Rome—referring to them as “sister churches.” This language underscores the image of the Church “breathing with both lungs,” acknowledging the indispensable spiritual and historical contributions of both Eastern and Western Christian traditions.
The phrase Ut unum sint itself, which means “that they may be one,” draws from Christ’s prayer for unity and continues to inspire efforts toward ecclesial reconciliation decades after its publication. While some challenges remain, Deacon Galadza points to important strides made over the years, including papal apologies to Orthodox Churches and the return of relics to the Patriarchate of Constantinople, gestures that have fostered goodwill and dialogue.
The presence of Orthodox patriarchs and delegations at papal ceremonies, now almost routine, serves as a tangible symbol of the vision behind Ut unum sint becoming part of the Church’s everyday life. This growing closeness signals hope for eventual communion, affirming that “all may be one” is not merely an ideal but an unfolding reality.
In recent years, numerous theological dialogues and documents have addressed thorny issues such as the Filioque clause and papal primacy, while discussions about intercommunion continue to develop. These conversations reflect the ongoing work of healing centuries-old divisions and building mutual understanding.
Pope Leo XIV’s pontificate has already embraced relations with Eastern Christians as a key focus. One of his first major acts was a jubilee audience for members of the Eastern Catholic Churches, an event that Deacon Galadza described as “providential” and deeply symbolic. Although the gathering primarily included those in communion with Rome, its tone and message extended implicitly to all Eastern Christians, reinforcing their shared vocation to work toward unity.
During this audience, Pope Leo quoted revered Greek saints such as Isaac of Nineveh and Simeon the New Theologian, and recalled Pope Leo XIII’s historical ban on Latin clergy proselytizing Eastern Christians—demonstrating sensitivity to the particular histories and identities of these Churches. The Pope also expressed concern for Eastern Christian communities in conflict zones like the Holy Land, Ukraine, and Tigray, highlighting how appeals for peace resonate across ecclesial boundaries.
Looking ahead, Deacon Galadza acknowledged that the quest for unity remains a hopeful aspiration, sometimes distant yet increasingly tangible. The Ecumenical Patriarch’s presence at Pope Leo’s inauguration exemplifies this hopeful progress, a sign that the prayer of Christ for unity might one day be fully realized “at the altar through the Eucharist.”
As Ut unum sint turns thirty, the Catholic Church’s ecumenical mission continues with renewed vigor, striving to fulfill the prayer and promise of one Church living in communion, diversity, and peace.