The original sin

Someone asked me a question on the weekend which I wasn't able to answer then and haven't been able to answer since - even though I have been seeking advice from others, and doing some net research. The question: what is the equivalent one-word noun for not committing a sin. The best to emerge so far is "good deed" or the Jewish "mitzvah" but it seems that if the powers that be wanted to encourage people to do good, there should be a word to acknowledge the act. Any ideas? Especially since there are a few for sin - trespass, transgression to name a couple. (Or does it make it easier for the Church to heap guilt on people if they only have a word for "sin" as someone suggested?)