This book offers a generative and hospitable theological methodology rooted in the distinctives of pentecostal spirituality, enlivened by a Spirited imagination and opened toward critical, constructive, and conciliatory dialogue with the wider Christian tradition. This inter- and cross-disciplinary work is careful yet generous, drawing together of knowledge and wisdom from different domains-historical, philosophical, and theological-in ways recognizably pentecostal and effectively missional. The book begins with a description of the essence of pentecostal spirituality that holds true across the various pentecostalisms. Drawing largely on an innovative engagement with the insights of Rudolph Otto and an exploration of the dialectic between religious experience and theological development, this book contends for an identifiable but mysterious "something" that makes pentecostalism truly pentecostal-that is, something more than one might sum up in any set of peculiar practices, beliefs, or behaviors. The book also provides an overview of the intellectual history of English-speaking pentecostalism, specifying and assessing the movement's major philosophical underpinnings and socio-cultural motivations. Finally, funded by an explicitly pentecostal metaphysics, the book sets forth a significant and boldly original pneumatological theological methodology, shaped by discerning conversation with the works of Amos Yong, L. William Oliverio, Jr., Wolfgang Vondey, and Simo Frestadius, among others.