The comment didn't necessarily mean anything. A lot of people who weren't Catholic gave gave up things for Lent, but if he had to guess (and Giotto was pretty good at guessing) she probably was. It might not be true that, as the old saying went, there were no atheists in foxholes, but it was true that people in Security and Tactical tended to be more religious on average. You couldn't be a good CO and not respect that or have at least some knowledge of the major 'name brands'. In the case of Catholicism Sam knew more than he really cared to, but even if 'lapsed' was probably the most charitable adjective that could be applied to describe him as a Catholic, he did have a certain appreciation for the faith.
"If it's any help," he offered. "I know I Jesuit who always says that it's 'better to give than to give up'. Of course being a priest, he has to give something up, but he usually chooses something that leaves him extra time to do more for others."
When she picked up the roller, he started handing over rectangles of dough. "Here. Put a bit of flour on the roller and squeeze the edges together around it. Not too tight though - it has to slide off."