In Mere Christianity, C. S. Lewis leads all the Christian religions to common ground. This book is in fact a defense of the beliefs common to all Christians at all times. Originally, these ideas were contained in three separate books. Prior to 1943 they were only heard as informal radio broadcasts. This is why you will see colloquialisms used and the conversational style of the writing.

When you read C. S. Lewis' work, you can hear his voice. Sometimes I forget I am reading. Like a friend with a cup of coffee in hand, he sits across from us. He then leads us up a ladder of logical thinking. He starts on the lowest step and gives us confidence to climb the next step. He guides us through an incredible thought process to a conclusion, which is perhaps so logical it becomes irrevocable truth.      Amazon Review by ~TheRebeccaReview.com

This is the whole book on this one audio link (almost 6 hrs):    

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