Sorry the Amazon link is broke 

This is the book that I wish I had a long time ago.  Very well written.  Easy to understand.  It’s written in a “catechism on the Catechism” format.  Lots of questions and answers on each question in the Westminster Larger Catechism. 

While the Larger Catechism itself is an outstanding work that carefully and succinctly explains our Christian faith, this is a work that takes each question and breaks it down further.  Insightful commentary and fitting Scripture citations round out each selection and make this an easy to use resource for quick reference.  Highly recommended.