The hidden Jewish law woven into your clothes

(RNS) — In the weeks leading up to Rosh Hashanah, the two-day Jewish New Year’s holiday that begins at sundown on Sept. 11, Chava Goldberg spent much of her time at her sewing desk, gently opening the linings, collars and waistbands of her clients’ suits, hats and dresses in search of “shatnez ” — the forbidden mixture of sheep’s wool and linen in a single garment.

A resident of Norfolk, Virginia, Goldberg, an interior designer by profession, is one of just 200-250 specialists in the world qualified to inspect clothing for shatnez, which the Torah bans in Leviticus 19:19 and Deuteronomy 22:11.

The High Holiday period “is especially hectic,” Goldberg said, because observant Jews traditionally purchase new clothes to usher in the Jewish New Year.

The prohibition against wearing shatnez is one of the Torah’s 613 commandments , along with observing the Sabbath, honoring one’s parents and worshipping one God, but it is not widely known outside Orthodox Jewish circles. Unlike commandments with more readily apparent ethical purposes, shatnez belongs to a category of commandments (“mitzvot” in Hebrew) whose reasons aren’t obvious.

“There are reasons for every mitzvah. Some are apparent and some are not,” said Rabbi Ezra Sarna, director of Torah and Halacha Initiatives at the Orthodox Union, which recently organized a conference for shatnez testers.

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One theory is linked to the biblical story of Cain and Abel: As an offering, Abel sacrificed sheep, which produce wool, while Cain brought a sacrifice of flax, the source material of linen. The two brothers were at odds with each other. Meanwhile, Maimonides, the renowned scholar of Jewish law, believed the prohibition refers to idolatrous priests, whose practices are forbidden to Jews.

Until the Industrial Revolution, most cloth was homespun or locally produced and sewn into clothing locally, often by Orthodox Jews, so most garments were not tested for shatnez.

But as the production of most textiles and garments has gone global and manufacturers now use threads composed of several different types of fibers, the demand for shatnez testers has steadily grown.

Joseph Rosenberger, an Austrian Holocaust survivor who immigrated to the U.S. in the 1940s, revived the practice after realizing that textiles and clothing in Europe and North America were largely mass produced. He opened the first shatnez laboratory in the U.S. soon after.

Rabbi Yosef Sayagh, director of the International Association of Professional Shatnez Labs, has helped shatnez testing become much more mainstream by training about 250 Jewish men and women to serve as shatnez testers all over the world.

About 150 shatnez testers are currently working in North America. Most are graduates of Sayagh’s 40-hour course in Lakewood, New Jersey, which focuses on textile science, microscopy and Jewish law. Students learn how to identify fibers by appearance, texture and microscopic examination before undergoing further independent study and certification.

While most of the items they examine are worn on the body, many rabbis say the prohibition extends to anything that provides benefit to the body, including rugs, carpets, pillows, couches, quilts and even baseball gloves.

Testers must examine up to three dozen hidden structural components, from collar reinforcements and cuffs to shoulder pads, linings and waistbands, composed of or filled with a wide variety of threads (often blended) and fabrics, each manufactured separately from the visible outer fabric.

Testers cannot rely on clothing labels, Sarna said, because they generally identify only the visible shell fabric, not the internal construction.

“The shirt you’re wearing right now might be a polyester, rayon, cotton, wool blend,” Sarna said. “Many clothing items have supports or pads inside that the person wearing it doesn’t even notice. Those support materials could be made out of anything.”

Rabbi Mordechai Djavaheri, who teaches experiential areas of Jewish law at Yeshiva University, decided to become a tester because there is currently no one in upper Manhattan to carry out testing. He is half-way through the course.

“In Riverdale and Washington Heights, we have many young professionals and so many young families who need shatnez testing, but they have to go to Queens or Brooklyn or New Jersey in order to get their stuff checked.”

Djavaheri said it takes him between one-and-a-half to two hours to examine an entire suit but that very experienced checkers need 20 to 40 minutes.

Even when certified, checking for shatnez will only be a sideline, he said. “The money people pay me is a little extra,” Djavaheri said. “I do this for the community.”

Amy Teifer, a Manhattan resident who works in New York City’s Garment District, dreams of starting her own shatnez-free line of clothing and hats. She is studying the trade “because, if I want to make sure that my garments are halachically certified as shatnez-free, I would have to leave Manhattan” to have the items checked. “I thought, why not do it myself?”

Goldberg, who became a certified tester several years ago, said the work is highly technical. To examine the innards of a hat, “you have to take the seam and remove the glue and fabric without leaving a residue.” For suits, “some of the primary points are going to be the felt under the collar, the canvas that stabilizes the jacket lapels and the shoulder pads.”

Several years ago, Sarna noted, hidden linen reinforcement materials were discovered inside certain production runs of sheepskin boots. Such discoveries do not mean that every item from a particular manufacturer contains shatnez. Materials and suppliers often change from one production batch to another.

The price and quality of an item — or assurances by the manufacturer or seller — are also no guarantee that a garment is free of shatnez, Sarna said.

“There are no real records of what materials are going into each piece of clothing,” the rabbi said. “It just doesn’t exist. The OU (Orthodox Union) has sent rabbis to China to look at different textile factories to see if there’s any way to create a contained environment so we can certify clothing. We’re actively searching for solutions.”

In the meantime, shatnez testers do everything they can to identify and solve the problem, so Jews can fulfill this Torah commandment. Often, a tailor can remove the prohibited piece; other times not.

Goldberg said the trust people place in her is a great responsibility. “I don’t want somebody walking around with shatnez because of me. So, I take my time and I’m very deliberate and very careful. It makes me feel good that people are aware of the mitzvah.”

Djavaheri said he is happy when he can enable a fellow Jew to perform a commandment.

“Doing so allows me to fulfill my role as a teacher of Torah who guides people to be more committed to Jewish observance,” he said. “Helping other people do the mitzvah is definitely satisfying.”