The Hans Anderson story of "The Red Shoes" illustrates the consequences of being lured by vanity and forgetting one's duties and obligations. What seemed a harmless pair of shoes, something that could make her feel better about herself, became a young woman's burden and bane. The Devil is a reminder that those tempting, quick fixes can become our addictions and obsessions that cause more problems than they solve.
The Kashmirian rowan tree, with golden russet foliage and white berries, is one of the last trees to lose its leaves in the autumn. It seems to stand as a symbol for last chances among the other bare trees. Lewis associates it with grace, a word often used to represent mercy that comes with surrender. In the story above, such surrender came with acknowledgment and sacrifice (the loss of her feet). I personally choose to think of grace as the shrinking of my ego; it is a matter of acceptance rather than earning something. Anne Lamott explains it well:
It's the help you receive when you have no bright ideas left, when you are empty and desperate and have discovered that your best thinking and most charming charm have failed you. Grace is the light or electricity or juice or breeze that takes you from that isolated place and puts you with others who are as startled and embarrassed and eventually grateful as you are to be there.