ROME – As Pope Benedict XVI was laid to rest Thursday in the Vatican, Christian and interfaith leaders across the world conveyed their appreciation of his theological contributions and efforts to build bridges.

In a statement of condolence, the acting Secretary General of the World Council of Churches (WCC), Reverend Jerry Pillay, said the former pope’s theological, pastoral, and ecumenical legacy “remains forever.”

“At the heart of his spiritual leadership was the promotion of a culture of peace and global solidarity,” he said, saying Benedict as pope “encouraged deeper understanding and cooperation with different Christian communions that trace their roots back to the Reformation as well as with the Orthodox Church, by stressing the significant elements of shared faith.”

Pillay noted that Benedict XVI was the first pope to ever belong to a WCC committee, the Faith and Order commission, at the time when then-Monsignor Josef Ratzinger was serving as a professor of theology at the University of Tübingen in the late 1960s.

“He not only brought an important theological contribution, but also showed the irreversible journey of the Catholic Church in the one ecumenical movement, for which we are truly grateful,” Pillay said, saying Benedict will remain “one of the finest and renowned theologians of the 21st century.”

Benedict, he said, was “an inspired spiritual leader who committed himself to a common and prophetic voice of Christians in the face of societal challenge. He was a man of deep faith, who cultivated humbleness and a servant leadership.”

Similarly, the Dalai Lama in his own letter of condolence to the Vatican’s embassy in New Delhi voiced sadness at Benedict’s passing, saying when he and Benedict met, “I found there was much we agreed about in relation to human values, religious harmony and the environment.”

“During his papacy, he worked hard to promote these issues. He lived a meaningful life,” the Dalai Lama said, saying he has been engaged with the Catholic Church for decades and has “learnt much about their experience,” and that “these exchanges have contributed to a better religious understanding between us.”

“At a time when we are seeing tension in several parts of the world, we can take a lesson from the life of Pope Benedict and do what we can to contribute to religious harmony and global peace,” he said.

Benedict died Dec. 31 at the age of 95, nearly 10 years after making history for becoming the first pope in 600 years to resign from the papacy.

Since Monday, devotees, tourists, and curious outsiders have flocked to St. Peter’s Basilica, where Benedict XVI was lying in state until his funeral Thursday morning, which will mark the first time a pope has celebrated the funeral of an emeritus pope.

In the days since his passing, Benedict has been hailed for his intellectual and theological contributions to the global church and is already being called one of the most influential thinkers of the late 20th and early 21st centuries.

While Pope Francis has become known as the pope of ecumenism for his very intentional efforts to build bridges with other branches of Christianity, ecumenical and interfaith leaders are have also praised Pope Benedict as having laid part of the foundation on which Francis is building.

In her own statement of condolence for Benedict’s passing, Reverend Anne Burghardt, secretary general of the World Lutheran Federation (LWF) called the pope emeritus “a sharp-minded theologian whose strong academic background shaped his pontificate.”

“We give thanks for his encouragement never to slacken in the ecumenical endeavor,” she said, expressing gratitude for the times Benedict voiced appreciation for the 1999 joint Declaration of Doctrine of Justification, which she said, “has enabled many advances in Lutheran-Roman Catholic relations.”

Burghardt pointed to then-Cardinal Ratzinger’s involvement with discussions between the LWF while still head of the Vatican’s Dicastery for the Doctrine of the Faith, “working with a group of German theologians to ensure a consensus on the Joint Declaration, following the publication of reservations from the Catholic side.”

The joint declaration has since been signed by several other major Christian organizations, including the World Methodist Council and the Anglican Communion, as well as World Communion of Reformed Churches, “making it one of the most significant ecumenical documents for multilateral worship, action and theological engagement,” thanks in part to Ratzinger’s efforts, she said.

In a statement, the Archbishop of Canterbury, Justin Welby, noted that Benedict in his lengthy life and ministry “saw many profound changes in the church and in the world,” having lived through German Nazism, the Second World War, and the Second Vatican Council, as well as the fall of the Berlin Wall.

“Pope Benedict was one of the greatest theologians of his age – committed to the faith of the Church and stalwart in its defense,” Welby said, saying, “In all things, not least in his writing and his preaching, he looked to Jesus Christ, the image of the invisible God.”

“It was abundantly clear that Christ was the root of his thought and the basis of his prayer,” he said.

Several Orthodox leaders have also voiced their appreciation for Benedict XVI, and sorrow for his passing, including Russian Orthodox Patriarch Kirill, who has come under fire from the global community in recent months for his support of Russia’s invasion of Ukraine earlier this year.

In a statement, Kirill voiced sadness at Benedict’s passing, saying his many years of life “marked an entire era in the history of the Roman Catholic Church, which he guided in a historically difficult period, associated with many external and internal challenges.”

“The indisputable authority of Benedict XVI as an eminent theologian has enabled him to make a significant contribution to the development of inter-Christian cooperation, to the witness of Christ in the face of a secularized world and to the defense of traditional moral values,” Kirill said, saying he saw first-hand in his meetings with Benedict “his deep love for eastern Christianity.”

He also praised Benedict’s “sincere respect for the tradition of Russian Orthodoxy,” saying that during Benedict XVI’s papacy, “relations between the Russian Orthodox Church and the Roman Catholic Church developed considerably in the spirit of fraternal collaboration and in the desire of fraternal collaboration.”

Similarly, Patriarch Bartholomew of Constantinople during a Divine Liturgy on Jan. 1, recalled the many times he worked with Benedict, including the signing of a joint declaration during Benedict’s visit to Turkey in 2006.

“Benedict XVI was a great theologian,” he said, noting that Benedict while still a university professor had Orthodox students, including the now-Archbishop Stylianos of Australia and the then-metropolitan of Switzerland, Damascene.

“I myself have heard from Benedict that he got to know Orthodoxy better thanks to his Orthodox students,” Bartholomew said, asking that the memory of Benedict be “everlasting.”

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