1 Corinthians 9:24-27

He sacrifices everything to the one end, if he can only carry off those much coveted laurels. And so a man must sacrifice himself, his own prejudices and predilections, and self-esteem, if he is to gain that immortal chaplet. That is the secret of my life. I do not hit out at random, but I go to work in a scientific manner, like one who trains for a boxing match. My blows are well and cunningly directed. They are aimed at myself, my physical being, my physical ego; otherwise what guarantee is there that I shall be saved myself, even though I have preached to others.