1 Corinthians 9:24-27

24Do you not know that in a race all the runners run, but only one receives the prize? Run in such a way as to take the prize. 25Everyone who competes in the games trains with strict discipline. They do it for a crown that is perishable, but we do it for a crown that is imperishable. 26Therefore I do not run aimlessly; I do not fight like I am beating the air. 27No, I discipline my body and make it my slave, so that after I have preached to others, I myself will not be disqualified.