1 Corinthians 9:26 ASV

²⁴  Know ye not that they that run in a race run all, but one receiveth the prize? Even so run; that ye may attain.

²⁵  And every man that striveth in the games exerciseth self-control in all things. Now they 'do it' to receive a corruptible crown; but we an incorruptible.

²⁶  I therefore so run, as not uncertainly; so fight I, as not beating the air:

²⁷  but I buffet my body, and bring it into bondage: lest by any means, after that I have preached to others, I myself should be rejected.