What is Judaism? A religion? A faith? A way of life? A set of beliefs? A collection of commands? A culture? A civilization? It is all these, but it is emphatically something more. It is a way of thinking about life, a constellation of ideas. One might think that the ideas Judaism introduced into the world have become part of the common intellectual heritage of humankind, at least of the West. Yet this is not the case. Some of them have been lost over time; others the West never fully understood. Yet these ideas remain as important as ever before, and perhaps even more so. In this inspiring work, Rabbi Sacks introduces his readers to one Life-Changing Idea from each of the weekly parashot.