Mere Christianity

C.S. Lewis professes not to be a religious leader. Instead, he presents an intellectually rigorous layman's view of Christianity.
His attempt is to provide an intellectual foundation for Christianity regardless of sect. He points out that science can know everything about the entire Universe, yet still not know where the universe came from. With God "outside" the known universe, we would not expect to find fully about him through scientific inquiry.

He brings few additional interesting analogies for Christian principles. He uses the "dimensionality" argument to explain the lack of "time" in God's world. (He can move along dimensions around us.) He also analysis sexual urges by comparing it to food. While we all eat, we don't have food strip-teases or similar things as with sexual desire.

It provides many other good "arguments" for Christian principles (including the resurrection) that help make them clear from the point of view of somebody inside or outside of a Christian sect.