My favorite writing by C.S. Lewis is an essay, published in a small book that I read for the first time, 30 years ago, after I read the entire Chronicles of Narnia (which he wrote for his 12-year old niece) and the Space trilogy. It's called "The Great Divorce". It's an allegory about the reality of heaven and hell. I especially like the concepts that the people of heaven are bright, solid people and those from hell are insubstantial phantoms.
He shows the results of our choices. The solid people attempt to explain the grace of God to the phantoms. The phantoms choose unwisely based on selfish motives, to take their own road and expect Heaven to accept them anyway. We see humorously, the sillines of having it our own way. As Mr. Lewis contrasts the folly of man to the grace of God, we can see the more common things that keep us apart from God's love. He illustrates something that every lost soul prefers to Joy--having their own way and determining their own fate. Our Lord honors the choices of individuals.
I would recommend this book to those intelligent people with objections to the Christian faith due to a subjective moral position. Those who reject Christianity because they think it is too rigid are the most likely to get a lot out of the book. For those who are philosophical and good thinkers this book will stimulate their imagination in many ways. It will challenge their presuppositions. It will give them a good understanding of the Christian position in a non threatening way.
We make choices every day, every moment. Lord, Jesus, let me choose You.