Will Gives Out First
I can remember trying out for the cross country team at my high school. I could not understand how some of these guys did it. they could run and be fine at the finish line. I on the other hand was literally dying and giving up a mile short. The coach told me that the great runners understood that their will gives out long before their bodies, so they would persevere.
That helped me, I learned that the contest was not necessarily one of strength but rather one of will.
(From Christopher Nerreau's Sermon "Don't Lose Heart")