On Saturday, my wife and I got to see a performance of Les Miserables in Riverside (which was excellent, by the way). On the way home, someone had graffitied a freeway underpass with "Happiness follows right living." I found it rather ironic that we saw that right after Les Miz. As Laci said, "That's Javert."
"Right living" (if groups of people can even come to a clear consensus on that) can lead to fewer problems in life. From that perspective, it matches up with some research indicating earning up to $75-80,000 per year increases happiness. The explanation is that basic needs are met, which lowers anxiety and therefore can increase happiness. So it makes sense that happiness could be increased by causing fewer problems for ourselves.
Let's take Les Miz again as an example. Valjean made some mistakes. They definitely impacted his happiness. But it wasn't right living that improved his happiness. It was being given compassionate grace when he didn't deserve it, didn't ask for it, and didn't even do something to accept it. And I would argue the ultimate right living that led to happiness was giving love and grace.
Contrast that with Javert, the quintessential Pharisee. He, like Paul, lived according to the law as best as any human could. He was blameless. But was he happy? Not at all.
In fact, the climax of the Valjean/Javert storyline is focused around this topic of right living. Javert has lived rightly in his definition--according to the law. But he has virtually nothing to show for it. In contrast, Valjean has not lived rightly. But he has thrived. He has made a meaningful life for himself. This is what completely confounds Javert--he believes once a criminal, always a criminal.
Many people, especially with Christianity, believe that if we do everything right, things will work out great. There is some truth to it, but I've seen (and experienced) my fair share of this formula not working. Right living does not necessarily lead to happiness.
The other consideration is the relationship of happiness and meaning. We discussed this in Sunday school last week, and there's some good research articles on the topic. Ultimately, I would argue meaning is more important than happiness and can lead to happiness, but happiness won't lead to meaning. I'm not convinced rule following or right living will lead to meaning, either. That doesn't mean we break rules--they are there for a reason.
I would propose that we need to recognize the law and rules for what they are: Something practical to help social cohesion and dynamics. But right living is not about law. Rather, I would argue that Christians should define right living in terms of love. To quote the end of Les Miz: "To love another person is to see the face of God." That sometimes means breaking some rules. And love is central to meaning-making (both philosophically and from research).
I would rather break a rule in favor of love and compassion and thus make meaning at the expense of some happiness and comfort than maintain the law and live like Javert.