<jats:p>Oswald Bayers suggestion to use the catechism as a basis for systematic theology is one of a series of attempts to answer the question What is theology? The essays in this volume accept this challenge in multifaceted aspects by using the catechism as their basis for orientation. The objective of the title Catechism as a Realm of Thought is to point out that such an orientation opens up large avenues of thought and of responsibility.</jats:p>