The Rambam in Hilchot Teshuva, makes a very important point. He wanted to make it clear that repentance is not limited to forbidden acts that we may have done.
He writes that just as we have an obligation to do Teshuva for such forbidden acts as stealing or immoral behavior, we also must repent in terms of our character flaws.
Teshuva is necessary for not controlling our anger, or for being jealous of others, or overly competitive. Or, perhaps we put too much emphasis on physical self indulgences. We must do Teshuva for everything.
The Rambam recognizes that changing bad habits and our negative personality traits, might even be more difficult than stopping to do forbidden acts.
Rav Yisrael Salanter once said, “The loudest sound in the world, is the sound of a bad habit breaking!” This requires very hard work and determination, to make these changes.
The beauty of the Mussar books, is how they provide us with the reminders that we need. For example, if we read on a regular basis, the horrible effects of not controlling one’s כעס, anger, then this will remain in a person’s head. He will have a conscious awareness that he must not get angry.
If one does not study these books, and does not have these reminders, he might get angry on a regular basis. If you ask him if he thought losing his temper was a good thing, he will agree that it is not.
Had he been given the proper tools, there could have been a better outcome. May the coming year be one in which we do Teshuva, and fix our character flaws.