When I recently met Rabbi Shmuley Boteach in Central Park, he was wearing Ray-Bans with tight black biking spandex and smoking a cigar. “There’s no pork in my cycling outfit,” he said when I asked him about the attire. “There’s no hidden crucifix. So I can’t imagine that I’m doing anything wrong. Plenty of rabbis love cycling.”  

You could sub in “sex”  for “cycling,” and you’d have Boteach’s stance on why there’s no conflict about his dual roles as ultra-orthodox rabbi and ultra-orthodox Dr. Ruth. He’s the author of books Kosher Sex and Kosher Adultery. His sex counseling reality show—"Shalom at Home" on TLC, in which he moves into the homes of troubled couples for a week and coaches them on their relationships, is scheduled to launch in Canada later this month, and last month began airing in Israel. Oprah is a big fan and gave him a talk show on her XM station.

Earlier this year he published his latest book, Kosher Lust, in which he argues that love alone can’t keep a marriage together: Great sex , he argues, is the glue that keeps couples strong. Science of Us spoke with him about this philosophy and about how secular couples can apply ultra-orthodox sex tips to their own lives.

Let’s talk about sex in the orthodox community, which you say can be hot.

I know what people say: “You guys are so frigid and inhibited." It’s absolutely not true. Among us religious Jews, sex is a big deal. It’s a religious obligation. In Jewish law, a man has to make his wife orgasm before he does.

Really?

It’s in the Talmud.

Do the scriptures weigh in on other specifics, like one position over another?

All positions are great. You can do circus acrobatics. But nothing can supplant the intimacy of the missionary position. Jewish law says there has to be full-body contact. Sex is supposed to be "bone of one bone, flesh of one flesh." The Zohar [a kabbalistic text] says you’re supposed to kiss, exchange breaths, and look into each other’s eyes. Religious Jewish couples are supposed to practice eyes-open sex.

Orthodox women don’t have a reputation for flaunting their sexiness.

The average Western couples are left with only three erogenous zones. On a man’s body, it is basically his genitalia, the tush, and on a woman’s body, you get one more, her breasts. In Orthodox Jewish circles, you have others, like the woman’s hair [usually covered]. Hair is one of the sexiest things around. My wife has beautiful hair, thank God. She wears a wig, in public. But not around me. It’s ours.

You also believe that Orthodox women have something else going for them sexually: unavailability, which apparently drives Orthodox men crazy.

In orthodox Jewish marriage, there’s a part every single month when sex is forbidden. You’re not even allowed to touch. It’s 12 days out of every month: five days of menstruation, and seven days after.

You believe unavailability is good for every couple?

It’s not easy to keep, but it leads to lust.

So does that mean anything goes, as long as it stokes lust in a married couple?

Why not? Anything that makes you more hooked is permitted. Oral sex is fine. Anal? Yeah, why not? She wants S and M? Sure. What’s wrong with S and M? There’s nothing un-kosher about it. Sex toys are great. What’s wrong with sex toys? Anything that increases the passion of husband and wife, great. Have sex in middle of a golf course.

That’s quite an image. An orthodox couple on the back nine.

We all believe that great sex requires novelty. But I don’t think it’s the novelty of a new partner. I think it’s the novelty of going deeper into the erotic mind of the same partner, really understanding their fantasies. Give them an erotic quiz. A husband slowly gets his wife to trust him enough to open up about her erotic fantasies about other men, which are usually sinful, and usually exciting.

So you want people to cheat in their minds?

Have an affair with your wife. I want men to fantasize about their wives. And if they fantasize about their wives with other men to give them the variety they need, big deal. You don’t have to have a sanitary marriage. We tend to make the single years into the wild years. Marriage should be about swinging from the chandeliers.

This piece originally appeared on Science of Us, New York magazine's science blog.