This study is the first comprehensive history of the impact of the modern missionary movement on the understanding of and work toward Christian unity. It tells stories from all branches of the church: Roman Catholic, Orthodox, and Protestant in its many types (conciliar, evangelical, Pentecostal, and independent). Part 1, "Historical," highlights the contribution of modern missions to Christian unity, from William Carey and his antecedents and peers to present-day missions. Part 2, "Ten Models of Unity," takes an inductive approach to history, asking not "how should Christians cooperate?" but "how has the missionary movement helped Christians to work together at the local, national, regional, and global level?" Part 3, "Wider Ecumenism," broadens the evidence to include how the missions movement has helped not only institutional churches but also broader society to have concern for the unity of the entire human family. Included here is the story of how the Protestant missionary movement influenced the forming of the United Nations as well as the drafting of the Universal Declaration of Human Rights. The study also covers the movement's impact on Christian attitudes toward, and relations with, persons of other faiths. Mission and Unity is the standard reference work in the field for persons studying modern history, modern church history, missions, and ecumenics.

The work of uniting churches is slow, challenging, and multifaceted; and it changes in each generation and location. In this book, Josiah Baker studies the efforts of believers towards reconciliation as something significant for how we understand the church. He offers a theology for laborers, people for whom unity is not only an idea but a calling and sure hope. A Visible Unity is a study in systematic theology on the relation of ecumenical methodology to ecclesiological convergence, how acting together results in the churches being together. Ecumenical work informs ecclesiology because it involves the actions of Christians together in accordance with their shared views of the church. Whenever this work changes, the partnering churches change their relations and further resolve their divisions. Baker studies ecclesiology by telling stories about a person—the Pentecostal ecumenist Cecil Robeck—for Robeck’s decades of leadership in American and global ecumenical settings. By narrating his activities and analyzing his thought, the book offers a window into the interrelation of different portions of the ecumenical movement and how the movement has changed over the years. Baker compiles archival materials and personal interviews to tell stories about ecumenism never before published.