This book is a collection of new essays on Aquinas and Wittgenstein written by some of the leading theologians and philosophers of religion in the English-speaking world. It is inspired by ' and dedicated to the memory of - Victor Preller, whose powerful interpretations of these figures did much to prepare the ground for recent discussions of religious language, knowledge of God, the role of grace in human life, and the ethical significance of virtue. Grammar and Grace frees Aquinas from the trappings of traditional Thomism, just as it liberates Wittgenstein from the relativism of the Wittgensteinian fideists. But the book is no mere exercise in scholarly revisionism, for its main purpose is to advance our understanding of the issues on which texts like the Summa Theologiae and the Philosophical Investigations have a bearing. This book will be essential reading for all those interested in the interpretation of Aquinas and Wittgenstein, the interface of religion and ethics, and the dialogue between philosophy and theology.