"It's open to a certain degree of interpretation," she says. "I'm sure the book mentioned that it used to be a coded way of saying that the wife wasn't going to cheat on the husband and the husband wasn't going to tolerate adultery in the wife, but modern readings tend to be rather more open-ended... for me personally, I would say it means supporting each other in difficult decisions and helping each other find the right choices. But I'm Betan, so perhaps I'm missing something."