The essence of Shabbos is peace of mind. Our attitude on Shabbos should be as if all the work we need to do has already been completed. If you need to travel or do any kind of work, on Shabbos you should try to feel as if you have reached your destination and every single job you have to take care of has already been completed.

All the laws of Shabbos serve as a recipe for attaining peace of mind. Not only are we to refrain from doing any form of work, but we are enjoined not to even discuss anything that has a connection with work.