Rabbis have rarely generated so much excitement. At least not in the bedroom. For the first time, Orthodox Jews can buy sexual lubricants that have been declared kosher.

The US-made Wet range of lubes now has eight lines that have been given a religious stamp of approval, including its "Ecstasy" product. This means that rabbis from the Rabbinical Council of California have inspected Wet's 52,000 sq ft production plant and researched the origins of every ingredient to check none comes from items prohibited by kosher rules.

As with many great innovations, the lubricant resulted from personal motivation. Sean Smith, president of Trigg Laboratories, which produces Wet, converted to Judaism after marrying a Jewish-Israeli woman.

But what's the need for a kosher lubricant? Orthodox Jews spread all sorts of cosmetics over their bodies without checking they are kosher. From soaps to exfoliators, moisturisers to medical ointments, observant Jews can use whatever is sold on the mainstream market without checking its origins. Kosher laws don't apply to products for external use. In fact, according to guidelines by the respected kashrut certifier Star-K: "one may even apply non-kosher ingredients to one's lips, eg lipstick, lip balm."

The bottom line is that kosher certification is only relevant to Jews who swallow a product. Really, it's only necessary for the God-fearing who intentionally swallow it – but some strict observers go further and buy kosher products if there is a risk of accidentally swallowing them.

So although Orthodox Jews haven't been waiting for the rabbinic nod before using lubes, they have been limited in what they could do with them.

For hundreds of years the Jewish religious establishment has been divided on whether oral sex is allowed as part of a bedroom repertoire; it's still pretty taboo for public discourse – and the rabbis who have approved the lubes haven't spelled out whom their certification will benefit. But among Orthodox Jews the significance is clear – 14 years after Rabbi Shmuley Boteach struck a blow for openness by publishing his hit book Kosher Sex this is the first rabbinic innovation to help kosher oral sex. In eight flavours.