Part of Fielding's goal with Joseph Andrews is to analyze "the only source of the true ridiculous (as it appears to me) […] affectation" (Preface.15). We'd call that a lighthearted approach, to the point of even being flippant. Fielding definitely tackles serious themes, but he does it by constantly poking fun at his best characters—especially characters who take themselves too seriously (that's called "affectation"). Parson Adams is a great example of a pious parson, but he also wears a pretty obvious toupee.
What's it all leading toward? As you might have figured, Fielding wouldn't leave you hanging with pointless comedy. Instead, he sets out to school us all on hypocrisy, virtue, and true gentility. He doesn't hide his didacticism, either. Fielding is like your favorite funny teacher (or, ahem, all of us here at Shmoop) who always has a lesson behind his jokes. He wants you to learn something, but he doesn't want to be all lame and boring about it.