The essential message of teshuvah, and thus the moral message of this season in its entirety, is that human change is really possible. In the face of all our cynicism, all the versions of determinism (genetic, Freudian, economic, and all the rest) that serve as excuses for us not to try to get our lives in gear, the Yamim Noraim come each year to remind us that it is possible to change our lives, and that such renewal partakes of the gift of life itself.Every year, as we approach the High Holy Days, I reread Rabbi Art Green's* wonderful Foreward to S.Y. Agnon's Day's of Awe. If you're looking for something short (that is, not book-length) to really get you thinking about the upcoming holidays, you can't do better than this.
* Interestingly (well, interesting to me, anyway), I've been reading this piece for years, long before I became such a huge fan of Rabbi's Green's thought. I should have realized long ago what a genius Green is!