9 And now as Moroni had supposed that there should be men sent to the city of Nephihah, to the assistance of the people to maintain that city, and knowing that it was easier to keep the city from falling into the hands of the Lamanites than to retake it from them, he supposed that they would easily maintain that city.
This verse teaches two truths that we can apply to our own lives. First of all, it is much easier to maintain a habit or practice then it is to retake or require it. The cost of requisition is quite high. We must fight off bad habits and clear ground for good ones. And it is difficult to turn something back into a good habit. Far better not to lose the habit in the first place.
Second, it is easy to become overconfident in our strengths and to assume that they will never be taken. One senses a little bit of that arrogance in this description. And Moroni’s great previous success might have left him feeling somewhat invulnerable. This is a character trait that plagues all of us and one that we must strenuously combat against.