How is justice achieved between wives when entertaining a guest in the home?

The service of a woman to her husband's guests is a matter of differing opinions. If we say it is obligatory, then it falls upon the wife whose turn it is. If we say it is not obligatory, then the wife whose turn it is is more deserving of performing it voluntarily. If the wife whose turn it is refuses to serve the guests, and another wife volunteers, then the husband may visit the volunteering wife outside of her allotted turn for this purpose.