John Gerstner (1914-96) was a significant leader in the renewal of Presbyterian and Reformed evangelicalism in America during the second half of the twentieth century. Gerstner's work as a church historian sought to shape evangelicalism, but also northern mainline Presbyterianism. In order to promote evangelical thought he wrote, taught, lectured, debated, and preached widely. In pursuing his aims he promoted the work of the great colonial theologian Jonathan Edwards. He also defended and endorsed biblical inerrancy and the Old Princeton theology. Gerstner was a sharp critic of theological modernism and what he considered its negative influence on the church. Part of Gerstner's fame was his active participation in mainline Presbyterianism and in so many of the smaller Presbyterian denominations and in the wider evangelical movement. His renewal efforts within the United Presbyterian Church USA (later PCUSA) were largely a failure, but they did contribute to the surprising resurgence of Presbyterian and Reformed evangelicalism. Evangelical marginalization in the mainline led Gerstner and other evangelicals to redirect their energy into new evangelical institutions, groups, and denominations. Gerstner's evangelical United Presbyterian Church of North America (UPCNA) background influenced the young scholar and the legacy of the UPCNA's heritage can be detected in the popular forms of the Presbyterian and Reformed evangelical movement that exist today. Moreover, he was significant for the revival of Reformed teaching beyond the bounds of Presbyterianism. This book establishes Gerstner's significance in American church history and provides a thorough analysis of the evangelical movement he sought to reinvigorate. ""John Gerstner was a dynamo. His energy was mainly evident to those who heard him speak, but Jeffrey McDonald's careful biography comes just as close to capturing the vigor that informed the Pittsburgh professor's voice, heart, and mind. This book is a must read for anyone interested in Calvinistic evangelicalism after World War II."" --D. G. Hart, Distinguished Associate Professor of History, Hillsdale College, Michigan ""This well-researched book illuminates the career of a scholar, churchman, and memorable teacher who left a major mark on American Christian life."" --Mark Noll, Author of America's God: From Jonathan Edwards to Abraham Lincoln ""I commend his work to anyone who seeks a better grasp of orthodox reformed theology in mainline Presbyterian denominations in the twentieth century."" --Don MacLeod, Research Professor of Church History, Tyndale Theological Seminary, Toronto ""Jeff McDonald demonstrates that his subject, in company with a cohort of fellow United Presbyterians in western Pennsylvania, exercised an influence on American evangelicalism out of all proportion to their numbers."" -- Kenneth J. Stewart, Professor of Theological Studies, Covenant College, Georgia ""A well-researched and engaging biography that portrays the successes, failures, and enduring legacy of this key player in American Reformed evangelicalism."" --Bradley J. Longfield, Professor of Church History, University of Dubuque Theological Seminary ""This well-researched book illuminates the career of a scholar, churchman, and memorable teacher who left a major mark on American Christian life in the second half of the twentieth century. John Gerstner was sometimes on the losing side of debates among Presbyterians and evangelicals in which he took part, but Jeffrey McDonald explains clearly why those debates deserve careful attention from readers with any interest in the causes that drove Gerstner's career."" --Mark Noll, Author of America's God: From Jonathan Edwards to Abraham Lincoln ""John Gerstner, longtime professor of theology at Pittsburgh Theological Seminary, was a dynamo in the classroom, and as a conference speaker, writer, and church leader. His energy was mainly evident to those who heard him speak and prea