I'm currently reading Weight of Glory, a collection of addresses given by C S Lewis, including the title address. It has so far been one of the best things I've picked up by Lewis.
Some things I've read about so far to spark your interest and to encourage you to read it:
-Lewis' idea of transposition, that the 'higher' often expresses itself in the 'lower.' One particular case he considers is that of spiritual experience, with the 'higher' being the workings of the Spirit and the 'lower' as the emotions that might accompany them. He described those who can only see the 'lower' as a dog staring at a finger pointing at something, but all that he sees is a finger. He doesn't get its higher meaning.
-Lewis' view of scripture, which I find both controversial and palatable.
-The importance of myth and pagan religions.
-Having a secular work and sacred interest: "if you don't read good books, you will read bad ones."
Happy reading.
Evan