1 Corinthians 9:24-27 New King James Version (NKJV)
Striving for a Crown
24 Do you not know that those who run in a race all run, but one receives the prize? Run in such a way that you may [a]obtain it. 25 And everyone who competes for the prize [b]is temperate in all things. Now they do it to obtain a perishable crown, but we for an imperishable crown. 26 Therefore I run thus: not with uncertainty. Thus I fight: not as one who beats the air. 27 But I discipline my body and bring it into subjection, lest, when I have preached to others, I myself should become disqualified.
1 Corinthians 9:24-27 New International Version (NIV)
The Need for Self-Discipline
24 Do you not know that in a race all the runners run, but only one gets the prize? Run in such a way as to get the prize. 25 Everyone who competes in the games goes into strict training. They do it to get a crown that will not last, but we do it to get a crown that will last forever. 26 Therefore I do not run like someone running aimlessly; I do not fight like a boxer beating the air. 27 No, I strike a blow to my body and make it my slave so that after I have preached to others, I myself will not be disqualified for the prize.