Self-discipline
"Gut Check" is an excellent article promoting self-discipline in a recent issue of Breakaway magazine from Focus on the Family. Though written for teens, everyone will benefit. An excerpt:

"We all have some amount of self-discipline; the trick is to make it a lifestyle. Self-discipline is like mental muscle, and it has to be exercised if it’s going to grow.

In looking back on my own life’s biggest failures and most painful disappointments, it’s plain to see in hindsight that, for the most part, all of them could have been avoided if I had exercised self-discipline. In many cases, I knew exactly what I should have done, yet I didn’t do what was right. In other cases, I knew what I should not have done, yet I chose the stupid course of action anyway.

It all fell to the weakness of my will. Had I been stronger in character, I would have been able to make myself execute what I knew to be the best course of action. Whenever I make a habit of denying myself daily, forcing myself to do what needs to be done (especially when I don’t feel like it), I soon find that my entire life is in better shape than it was before. "