Most people recognize the name C.S. Lewis if only as the author of The Chronicles of Narnia. A few more may be familiar with another of his classics, Mere Christianity. Lewis, of course, was a towering intellect and wrote far more than those works but the Chronicles and Mere Christianity are what he is most remembered for.
I usually read Mere Christianity at least once every two years and sometimes more than that. It never grows old for me. Each reading is as fresh for me as the first. Occasionally I run across some fool who claims that Lewis' arguments in Mere Christianity fell flat for them. At that point I ask them which specific argument they found wanting and how they answer what Lewis posited. I never get a response.
I don't care what someone believes. I don't care if they are swayed by his writings or not. I do care when someone claims his argument's are weak and than offer no alternative. I suspect those people have never really read they book.
Lewis, who was a professor at Oxford and then later at Cambridge is himself now the subject of innumerable University level courses. It can be argued that Lewis had as much affect on the 20th century as Whitfield did on the 18th.
Paul McCusker has written a delightful book on how Mere Christianity came about that is in parts a shortened biography of C. S. Lewis, partly an account on how the book came to be written, and partly an account of WWII Britain. It is in each of its parts brilliant.
This too is a book I will read again. C. S. Lewis & Mere Christianity: The Crisis That Created a Classic is more than worth your time and money.