Christianity by C.S. Lewis
Lewis is as skillful as ever at explaining in laymen’s terms deep theological truths. Keep in mind, Lewis repeatedly reminds us that he is not a theologian. So don’t expect to get your systematics from him. That said, he shows us a great example of how to take deep theological truths and state them so almost anyone––of even average intelligence––”gets it.” He certainly has his moments where those who like their theology as punctiliar as a swiss watch will wince, but he would likely wince in return at their inability to state such precise theological notions in such a way as to make them understandable.
I think Lewis actually did something quite remarkable in Mere Christianity, which will be of immense profit to the church for ages to come. He may not be right on every point, but he gets to the heart of the fundamentals of what it means to be Christian. He contrasts it with various other religious and agnostic notions, and shows that Christianity is the best explanation for the world, and is most reasonable. He also drives home important devotional points for what it means to live like a Christian, and not only believe like a Christian.