I was out running earlier today, watching clouds build up overhead into a storm that is raging outside as I write this. And on my run, I let my mind wander into an epiphany (or, at least, a reminder of an epiphany that I had a while ago) ...
The mosaic law expressed in the Hebrew Torah was often used by the ancients as way of seeing identity as inextricably bound to what a person does. If you keep the sabbath, don't eat pork and wash your hands and feet in accordance with ceremonial custom, you are right with God. You're on a good track. This has its benefits: identity, as a fairly fluid, misty concept, is much easier to understand when it is tied to tangible outcomes.
Grace diffuses this concrete way of thinking – diffuses the self-assured nature of the law by pointing out that identity must first be bound to a state of being before it can be bound to a state of doing. Some of my students – designers, fine artists and philosophers in the making – often speak about their future careers in such as way as to give occupation a gravitas that I think is dangerous. I know so many people who choose a job based more on what they want to do than on who they are or what kind of person they want to be. This kind of thinking imbues work with only a temporary kind of value, because if a person gets bored or frustrated with what they do (which seems inevitable) they end up having a quarter-life or mid-life crisis. They end up coming face to face with a rather ugly reality: they don't know who they are. What they're busy doing has lost meaning even though it is not meaningless.
Grace undercuts the law, but does not negate it. It recognises that our actions are important, but also that they are only the surface. You can do good without being good. You can be polite with anger in your heart. You can speak clean words with corrupt thoughts. Grace points out that deeds are simply not enough by cutting through to the core, by telling us to identify ourselves, not by some external concrete system of values, but rather by a change of heart.