The Handbook of Religion and Health has become the seminal research text on religion, spirituality, and health, outlining a rational argument for the connection between religion and health. For the past two decades, this handbook has been the most cited of all references on religion and health. This Third Edition is the most scientifically rigorous edition to date, covering the best research published through 2021 with an emphasis on prospective studies and randomized controlled trials. This volume examines research on the relationship between religion and health outcomes, surveys the historical connections between religion and health, and discusses the distinction between the terms ''religion'' and ''spirituality'' in research and clinical practice. It reviews research on religion and mental health, literature on the mind-body relationship, and develops a model to explain how religious involvement may impact physical health through the mind-body mechanisms. It also explores the direct relationships between religion and physical health, covering such topics as immune and endocrine function, heart disease, hypertension and stroke, neurological disorders, cancer, and infectious diseases; and examines the consequences of illness including chronic pain, disability, and quality of life. Additionally, most of its 34 chapters conclude with clinical and community applications making this text relevant to both health care professionals and clergy. This book is the most insightful and authoritative resource available to anyone who wants to understand the relationship between religion and health.