CS Lewis

The controversy about faith and works is one that has gone on for a very long time, and it is a highly technical matter. I personally rely on the paradoxical text: "Work out your own salvation... for it is God that worketh in you." [Philippians 2:12] It looks as if in one sense we do nothing, and in another case we do a damned lot. "Work out your own salvation with fear and trembling," but you must have it in you before you can work it out.

You must be prepared for the unpleasant things and the discomforts... When you are training soldiers in maneuvers, you practice in blank ammunition because you would like them to have practice before meeting the real enemy. So we must practice in abstaining from pleasures which are not in themselves wicked. If you don't abstain from pleasure. you won't be good when the time comes along. It is purely a matter of practice.