I'm not Catholic, but the thought of giving up something for a certain amount of days seems very well...
"Tempting and controlling"
Tempting because the whole thought is about temptation and certain things that tempt you to force you to give up.
Control because you have to be in control to be able to resist temptation and learn that you can live without it.
I'm not a sweet tooth, so any kind of sweets, foods or other items would be just too "easy" to give up. I'm not too much of a shopper, where I don't spend money here and there, except for running related items.
So what am I giving up? I don't know yet...we'll figure it out...
What are you giving up?