The book I’ve been using this month for my daily devotional time (Be Thou My Vision by Jonathan Gibson–Book Review) includes a reading each day from one of the Reformed catechisms. I’m finding that to be a good exercise, and one that I would recommend to others. I had my husband (a Lutheran pastor) write an article about the why the catechism is important for teaching us the basics of the faith. It follows below.

A major concern for Luther and other Reformers was the level of ignorance about the basics of the Christian faith amongst lay people. This led to a number of different catechisms throughout the newly established Protestant churches. Luther published his Small Catechism in 1529. It was meant for use in the home where the father would teach his family and servants the fundamentals of the 10 Commandments, the Sacraments, the Lord’s Prayer, the Office of the Keys and the Apostle’s Creed. There was a short explanation of each of these topics.
Luther also wrote a Large Catechism which expands the teaching on the fundamentals and was intended for use by pastors and more educated adults. Both the Large and Small Catechisms are included in the Book of Concord, the Lutheran confessional documents.
Over the years the Small Catechism became the basis for confirmation studies and Luther’s goal of having it taught in the home fell into general disuse. This change led theologians to add more detail to the explanations as a teaching vehicle.
The Catechism itself spurred governments to expand free education so their people could read and understand them. In the 18th century the Danish/Norwegian king asked Erik Pontoppidan to write a detailed explanation of the Catechism which was then used as part of the public education in that realm. Pontoppidan’s work remains the basis for newer issues of the Catechism to this day.
P.S.(a note from Joan) In case you are interested in the origin of words, as I am (probably another English major trait), it comes from a Greek word, which simply means to teach or instruct, especially in a face-to-face manner.
For more about the Reformation see these posts:
How the Reformation Changed the Environment