The 30 August service was held at the Pentecostal Cathedral of Curico, Chile with WCC general secretary, Rev. Olav Fykse Tveit and the WCC president for Latin America and the Caribbean, Rev. Gloria Ulloa participating.
Church unity is one of the key goals of the WCC, which brings together some 500 Christians from mainly Anglican, Protestant and Orthodox traditions.
Unity was a key message in the service attended by more than 1,300 people.
Among the Protestant members of the WCC, Pentecostal and evangelical are growing but remain small in numbers.
There is "no other way" for his church but the one that leads to Christian unity, said Bishop Moraga whose Pentecostal Church of Chile is a member of the WCC.
"Despite occasional internal tensions around the question of churches' engagement in ecumenical movement, the commitment to be part of the global fellowship as an expression of faith prevails," he said.
The Pentecostal Church of Chile joined the WCC in 1961.
"Those who have hope have power to live and to participate in transformation of life, so that others can live with hope. Your church, Pentecostal Church of Chile, is a remarkable example of this truth, in the past decades under dictatorship as well as today," said Tveit.
The WCC area president Rev. Ulloa led the final prayer of the service.
The service in Curico gathered members of 12 congregations of the Pentecostal Church of Chile, including musicians and singers, the WCC said in a statement. The service was broadcast live on the church's website.
The WCC delegation also learned about the work of the Pentecostal Church of Chile, especially in the area of education for peace, care for creation, the work of the Shalom Center based in Alto Viches.
The meetings of the WCC delegation in Chile were part of the WCC Pilgrimage of Justice and Peace – a key area of its work since the 10th Assembly of the WCC at Busan, South Korea in 2013.
The delegates will continue their journey through Brazil and Colombia until 7 September.
Earlier on their visit the WCC delegates met Chilean President Michelle Bachelet including climate and gender justice in their discussion.
"The effects of climate change today and tomorrow will affect basic human rights," said Tveit during his meeting with Bachelet at the Palacio de la Moneda in Santiago on Aug. 29.
Tveit was accompanied by Ulloa and representatives of the two Lutheran churches from Chile, including Rev. Gloria Rojas Vargas from the Evangelical Lutheran Church of Chile and vice-president of the Lutheran World federation, chaplain of the Palacio de La Moneda.
Tveit explained ow the WCC has been pushing the climate change agenda at the United Nations Human Rights Council.
WCC delegates also heard the Chilean president's concerns on how climate change strongly affects lives of the most vulnerable communities in the country and beyond.
"Together with President Bachelet we talked about climate justice. It is very important that countries in the North and in the South deal with such issues as ecology, human rights and economic justice," said Tveit.
Bachelet served as the first under-secretary general and executive director of the United Nations women's program, established in 2010.