I've got a little slogan that I say it quite a bit; it might be good for you to take it. "A winner never quits, and a quitter never wins." Just think of it: "A winner never quits, and a quitter can't win." You must hold on. And before you even start, be dead sure you're right. And then be persistent. Let nothing move you. Go on. I've had quite a bit of experience of that, and you know it. But I know this one thing; when you're dead sure that you're in the will of God, when you're dead sure you're centered in Calvary, nothing's going to move you. You're there.

William Branham, Sermon "Perseverance"
http://www.en.branham.ru/sermons/63-0113E