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Fringe Movement: A Biblical Blue Makes a Comeback

The color purple – well, something related to it – is making a comeback, but its significance goes far beyond the favor of frum fashionistas.

A newly recovered biblical process of extracting the purplish blue dye from a Mediterranean mollusk is changing the way the commandment to wear tzitzit — the ritual fringes worn on the four-cornered prayer shawls — is being observed by some Modern Orthodox Jews and chasidim.

After a millennium and a half, it is now once again possible to include a blue (tekhelet) thread among one’s fringes, in accordance with God’s instructions to Moses in Numbers 15:38-39:

Speak to the Israelite people and instruct them to make for themselves fringes on the corners of their garments throughout the ages; let them attach a cord of tekhelet [blue] to the fringe at each corner. That shall be your fringe; look at it and recall all the commandments of the Lord and observe them.

How could a low-lying mollusk become the harbinger of innovation? In the biblical era, tzitzit fringes had one component dyed the color tekhelet. Associated in ancient times with royalty and the priestly caste, tekhelet was one of the few permanent dyes of the biblical era, made from a glandular secretion of the Murex snail called dibromoindirubin, which, after five to 10 minutes of exposure to air and sunlight, turns what’s called “biblical blue.”

It is unclear why usage of tekhelet diminished among Jews, though some would say it is in part because of the high cost of production, along with the Diasporic exile and loss of Jewish access to the necessary materials. Talmudic clues include a description of two Jews captured by the Romans for the crime of having “items made in Luz,” the Israeli city identified with the manufacture of tekhelet. There were other rulings against the plebeian population wearing colors deemed royal, including bans by Roman rulers such as Julius Caesar. Despite rabbinical efforts to maintain use of tekhelet, by the end of the first millennium it was considered lost. Since then, observant Jews have worn white tzitzit.

The dye’s revival is due in large part to the initiative and imagination — not to mention networking prowess — of several young Modern Orthodox professionals now living in Israel, mostly graduates of Yeshiva University’s science departments. Tekhelet has gained a following numbering in the thousands and the support of a diverse group of religious scholars, scientists and a few deep-sea-diving Croatian fishermen, looking to enhance their local economy.

Dr. Ari Greenspan is a resident of Efrat with a thriving dental practice in nearby Jerusalem and one of the founders of P’til Tekhelet Foundation (, which seeks to promote and distribute tekhelet. He told the Forward that his interest in tekhelet emerged from the desire to meld his creative urges with his interest in hidur mitzvah, or beautifying the ritual practice. Greenspan, an energetic 40-year-old who immigrated to Israel in 1988 from New Jersey, drew a particular pleasure from applying his manual dexterity to the fulfillment of Jewish law.

Several years ago, he began baking his own Passover matzo at his home in Efrat. The multitalented Greenspan — a practicing mohel and ritual slaughterer — has also contributed his handmade stained glass to his synagogue and is working on a book about tekhelet. His articles on the topic have appeared in the Bible Review and Chemical & Engineering News. He presented his research on contemporary halalchic applications at a recent symposium held at the Jerusalem restaurant Eucalyptus. There, he argued that the giraffe is indeed a kosher creature.

Greenspan was looking for another outlet for his energies when his friend Joel Guberman, who organizes tekhelet tours and deep-sea dives in Israel, told him about Rabbi Eliyahu Tevger.

Tevger immigrated to Israel from Russia in 1969. After learning of the mitzvah of tzitzit as a rabbinical student, Tevger became the first Jew in decades to pursue the topic seriously. Tevger — now a rabbi — traveled to the Mediterranean Sea about a decade ago, determined to uncover contemporary sources of tekhelet. It was there that he found the Murex snails.

After hearing about Tevger’s deep-sea dives along the northern Achziv coastal region in Israel, Greenspan grew excited. In no time, he found himself on a self-described “whim,” facedown and up to his elbows in the Mediterranean, searching for the mollusk alongside Tevger and physicist Baruch Sterman.

“To make a long story short,” Greenspan said, “we found something.” Using earlier historical research as their point of departure, Greenspan and a team of roughly a dozen confirmed that this was the same species of snail from which the original tekhelet dye had been made in biblical times.

Tracing the biological research of medieval dyers and talmudic celebrities such as Pliny the Elder, they were able to produce within a year “the first historical blue dye from the snail in over 1,500 years,” Greenspan said.

Today, tekhelet is created by extracting a yellowish “juice” from the Murex snail, which the foundation fishes in Europe. It takes about 10 to 30 snails to make enough dye for one set of tzitzit. The remaining snail parts are given to the local population gratis, to eat.

For the first year of their nonprofit venture, now the P’til Tekhelet Foundation, they created a home-based cottage industry, dyeing fringes on their patios. Word spread, and they opened a dye-production factory in Ma’ale Adumim to keep up with rising demands. More than a thousand visitors tour the facilities each year, with hundreds heading to the nearby Chof Dor beach for deep-sea snail diving.

Tekhelet is garnering followers after an exhaustive history of persistent research by notable figures.

Rabbi Moshe Tendler, talmudic scholar and biology professor at Yeshiva University, wears fringes dyed with tekhelet, as do his sons and grandsons.

Rabbi Tzvi Hersh Weinreb, executive vice president of the Orthodox Union, finds the material gathered by the P’til Tekhelet Foundation to be extremely convincing. He acknowledges that “sociologically, Halacha tends to be very conservative and tekhelet is an innovation, which people tend to resist because it’s new.” Furthermore, he pointed out that “many of us are convinced that this is a way to do the mitzvah completely.” For Weinreb, wearing tekhelet evokes “a sense of the tradition centuries ago — before it was lost.”

Rabbi Abraham J. Twerski, an author and psychiatrist, also supports the foundation’s work and appears in its promotional video.

“I feel an emotional connection with tekhelet, which is supposed to be a strong reminder of our relationship with Hashem, God,” Twerski said. Greenspan said that Rav Shlomo Dichovsky of the Beit Din Hagadol, Jerusalem’s Chief Rabbinate, also dons the dyed fringes.

One of the tekhelet project’s research foundations was the doctoral thesis of Isaac Halevi Herzog, Israel’s second chief rabbi. The multilingual 1913 University of London thesis, “Semitic Porphyrology,” discussed the production of purple and blue dye in ancient Israel. The thesis extended some of

the research of the Radzyner rebbe, Gershon Hanoch Leiner of Poland, who cited cuttlefish as the source of tekhelet. To this day, there remain followers of Leiner.

Objections to tekhelet fringes tend to fault the foundation’s historical research for incorrectly tying tekhelet to the Murex snail. A 2001 article published in the Journal of Halacha and Contemporary Society and posted on the, says that the Murex-produced tekhelet does not meet the standards set out in the Gemara and faults the foundation’s research as “inconclusive.”

For his part, Greenspan is quick to note that as a Modern Orthodox Jew, he is “unencumbered by the same fear of integrating the old and the new.” Greenspan says that the tekhelet revival has found enthusiasts in communities as far flung as Monsey, N.Y.; Teaneck, N.J.; London and even the Western Wall. A yearly growth in requests for tekhelet fringes supports the foundation’s claims that this movement is expanding to meet the demand for a creative application of an ancient tradition. More than 6,000 sets of tzitzit were shipped out this year (at 160 shekels each, or about $36).

“There’s something about tekhelet that touches a person’s soul,” he said. He notes this is borne out in letters his group has received from practitioners. “People feel wrapped up in the mitzvah of tzitzit or tallis when they put them on.”

Metaphors for tekhelet include the depth of the ocean and the blue of the sky and other imagery evoking the divine presence. “Tekhelet,” it says in the Talmud (Menachot, 43b), “resembles the sea, and the sea resembles the sky, and the sky resembles God’s holy throne.”

Few other mitzvot have such an array of visual images heightening the uplifting sense of their fulfillment. “It’s not mainstream, by any means,” Greenspan said. But, it’s also — no pun intended — “no longer a fringe issue, having made its way today to an object of discussion and great interest.”


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