Oops *soldier. Anyway, John offers to work (40 hours a week?) for rent. Bob says ok. After they have an agreed upon deal going for a few days, Bob says "Our deal was 40 hours a week 'for rent' (he made air-quotes and smiled). You have not been paying for my food that you have been eating. It'll be 80 hours a week now, making goods and services for me. Or get off my island."