Lance Maggiacomo was out of work, bored and lonely when he started hiding his online relationships from his wife.

There was no affair, only chatting through e-mail, yet it felt like cheating just the same.

A few years later, a reformed Maggiacomo has an in-house check on his impulses. He and his wife Lori, like other Christian couples around the country, share one e-mail account as a safeguard against the ever-expanding temptations of the Internet.

"There's not a Gestapo, KGB quality to it, like I have to check in with mother before I do anything," said Lance Maggiacomo, a 40-year-old surgical nurse from Beverly, Mass. "It's what we believe as Christians: We are our brothers' keepers. It's about biblical accountability."

The e-mail addresses — "tim—shawna" and "christyandbrian" — broadcast the couples' commitment to all correspondents. If one spouse has a Twitter or Facebook account, the other is usually given the password. Often, spouses have separate work accounts where bad behavior could go undetected. However, the goal isn't policing each other every minute, they say. Instead, they are doing whatever is possible to avoid keeping secrets.

"It's not a matter of distrust," said Ronda Hodge, 53, of Amesbury, Mass., an ice-cream maker who shares an e-mail address with her husband Tom, 60, a landscaper. "We really don't have anything to hide from one another. We were friends first before we even dated so we've got that level of openness there."

It's impossible to know how widespread the practice has become.

Couples with a joint account said they never heard preaching about it and didn't read it in an advice book. Some said they initially created their account for bills and other household business then later realized the personal benefits. A 2003 article published by the conservative Christian group Focus on the Family urged husbands and wives to share one e-mail address, but it was one of many suggestions on preventing infidelity.

Still, the phenomenon has become common enough to merit a post on "Stuff Christians Like," a popular blog in which creator Jonathan Acuff, an evangelical and son of a pastor, good-naturedly mocks Christian culture and himself.

Acuff shares one account with his wife of eight years, Jenny, and estimates that one-third of their married friends also use one e-mail address. He joked on the blog that he and his wife "cleaved our separate e-mail addresses and lit a unity candle on Yahoo! that burns brightly throughout the virtual landscape."

"We offset the whole thing by not dressing alike," he wrote.

In a recent phone interview from his home in Alpharetta, Ga., Acuff said he and Jenny started their account while planning their wedding, then noticed that it helped their communication, even in small ways, such as keeping track of each others' schedules.

He said he is grateful that his marital status is clear on his e-mail because he is in touch with so many strangers through his blog.

"It's so easy to make dumb mistakes online. We don't have this precedent for how these online friendships work," said Acuff, 33, whose posts will be released as a book by Zondervan next year. "For me, it's just a safety measure. I don't want to be just floating out there."

James Furrow, a professor of marital and family therapy at Fuller Theological Seminary, an evangelical school in Pasadena, Calif., said sharing an account can be helpful if the goal is promoting openness. But he said the practice can hurt a relationship if it's meant "as an act of deterrence."

"We can take steps to manage our behavior, but then the problem with that is it begins to become the emphasis rather than the trust of giving the other the benefit of the doubt," Furrow said. "What you end up with is the doubt."

Tim and Shawna Rollins of North Richland Hills, Texas, said they consider their shared account — "tim—shawna" — a sign of trust, not suspicion. Both were divorced and their first spouses had been unfaithful. The pair had been friends in high school, then began dating as adults, and entered their marriage pledging to share everything, no matter how uncomfortable.

"I'm just a real open book with him and likewise he is with me," said Shawna, 42, an administrator for a prison literacy ministry. "The trust is there. If he really wanted to do something he'd just do it. For us, it's just such a non-issue."

None of the couples could recall receiving an e-mail that was upsetting or started a fight. They said e-mail addresses with a husband's and wife's name can discourage old flames from trying to renew a connection. The couples said the only trouble they had was developing a system so that e-mails reached the right person or weren't accidentally deleted.

The Rev. Monica Mowdy, 48, and her husband Joe can't share one account because she is a pastor at the Friendship United Methodist Church in Cookeville, Tenn., and needs privacy for working with congregants. However, they know each other's passwords for e-mail and Facebook.

Mowdy, who has counseled many couples, said if the goal of sharing an e-mail is to check up on someone it's "inherently unhealthy." She and her husband decided to share their online lives because they believe too much privacy can build barriers.

This is the second marriage for both, and they wanted to share as much as possible so they could avoid bringing any distrust from their first marriages into their relationship.

"You get to the point where openness and daylight in a union becomes more critical than having your corner of privacy," Monica Mowdy said. "Whenever you have a place where you can keep secrets, the tendency is to keep secrets."