1 Corinthians 9:24 – 27

²⁴Know ye not that they which run in a race run all, but one receiveth the prize?  So run, that ye may obtain.  ²⁵And every man that striveth for the mastery is temperate in all things.  Now they do it to obtain a corruptible crown; but we an incorruptible.  ²⁶I therefore so run, not as uncertainly; so fight I, not as one that beateth the air:  ²⁷but I keep under my body, and bring it into subjection:  lest that by any means, when I have preached to others, I myself should be a castaway.