Q. Is it ethical to read my husband’s email? I don’t have reason to think he’s cheating, but I’ m the nervous type…

If you have no reason to suspect him, you would be putting far too much at risk by invading his privacy. You in fact would be the one guilty of betraying trust. Let it go.

In the 11th century, Rabbenu Gershom issued a ban of excommunication to those who opened other people’s mail. He also banned polygamy. So we can assume that until then, Jewish spouses did lots of opening each other’s mail and, as a result, they acquired lots more spouses. When Gershom said “enough is enough,” perhaps he saw the connection between invasions of privacy and the fragility of monogamy.

But while opening someone else’s snail mail is a clear breach of trust, e-mail is more complicated. One would assume that in all cases it would be forbidden to open an e-mail addressed to another. In the growing field of digital etiquette, the question of email and privacy is a big one. Unlike regular mail, email is by its nature not private. That e-missive you send traverses many networks before it reaches the recipient. Copies of the email remain on servers and hard drives. Employers routinely monitor staff e-mails. The rule of thumb is to assume that anything you write, once you send it anywhere online, could be seen by the entire world.

Email is as private as a postcard. When I was a camp counselor, I routinely read the postcards written by the kids in my bunk, just to make sure no one was sending home tear-stained sob stories about the camp food (or me). I don’t know if Gershom ever sent postcards from camp back then, or whether he would have included them in his ban. All I know is that my very ethical camp directors instructed me to read the kids’ postcards.

But even though email is not technically (or technologically) private, unlike a postcard it does have to be “opened,” so I suspect Rabbenu Gershom would still say it’s a no-no to read other people’s email.

You really have two compelling reasons not to open your spouse’s email: 1) he’s given you no reason not to trust him and 2) even if he were cheating, he’d be an absolute idiot to leave an email trail.

OK, so let’s assume that he’s an absolute idiot. If he’s that reckless, you’ll certainly find other clues to an affair in places that are not so private, like credit card bills and phone records; or in that lipstick on his collar.

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