The Power of ONE!!

When I interviewed a longtime friend for this project about the resurgence of observant Judaism in the 1960s, he gave me an unexpected explanation for the phenomenon: 

Think of it like the Chanukah miracle. It all started with the MESIRAT NEFESH (self-sacrifice) of one man, Matityahu. His determination sparked a revolution. I believe that the same thing happened in the 1950’s. A few dedicated, focused individuals were able to change the course of American Jewish history. ‘ 


But there was one man who single-handedly established the observance of a specific Torah mitzva, and that was a remarkable achievement. 

In the 1950s and early ’60s there were a number of mitzvot which went from rare to commonplace. For example: lulav/etrog, sukkot, glat kosher, shmurah matzo. However, I can only think of one mitzva performance which went from non-existent to well known, and that is Shatnez. 

It was due to the determined effort of one man. 

Joseph Rosenberger (usually addressed: Reb Yosef) was born in Austria, and, after spending five months in Dachau Concentration Camp, came to America in 1940. He lived until 1944 in an orphanage for young men in Brooklyn. His father had manufactured clothing in a suburb of Vienna, and he retained an interest in garments. But he was most intrigued about how to test for Shatnez in garments. He went to tailors around New York and discovered two facts: one, there was little knowledge about discerning the presence of linen in clothing, and two, there was little interest. No one cared! 

So, what is Shatnez? And why are we interested in a test for the presence of linen in clothing? 

Here’s the relevant Biblical verse:  

You are not to wear clothing woven with two kinds of thread, wool and linen together (Deuteronomy 22:11).  

That mixture is called Shatnez. 

There’s a little history of Shatnez in America. In Colonial times, the most widely used cloth was called ‘homespun’. It was made in defiance of British authorities who wanted the Colonists to import wool cloth from England. The other name for ‘homespun’? Linsey-Woolsey! Yes, the most popular cloth in early America had a linen warp with a woolen woof, or Shatnez 

As time went on this coarse but strong fiber went out of fashion, and most garments were made of either all cotton or all wool (this was before synthetics), but strong linen fiber was often used for thread or backings in collars or waist bands. 

So, Joseph Rosenberger was intent on finding a simple chemical test for the presence of linen in a wool garment. If you only wear cotton garments, you’re unaffected. 

Eventually, he found a simple, accurate reagent for linen. His next problem was more intractable: indifference! 

Reb Yosef went around to shuls in Manhattan and Brooklyn, offering free testing of garments for Shatnez, but no one was interested. Part of the problem was that many garments made of wool didn’t list linen in its contents, if it was only in the tread or backings. So, people were indifferent. Reb Yosef had to wake them up to the problem, because, even in small amounts, it was still prohibited from the Torah to wear such clothing. 

Eventually, he was introduced to Rabbi Herbert Goldstein, leader of the West Side Institutional Synagogue. Rav Goldstein was influential in the OU, having helped start its Kashrut division. He had written a letter on OU stationary back in 1941, warning about the potential for Shatnez in certain garments. It was the breakthrough Reb Yosef needed. Rav Goldstein got him in touch with garment producers, who could then advertise that their products were Shatnez-free. It was a beginning. 

With loans and other support, Reb Yosef opened his Shatnez Laboratory at 203 Lee Av, in Williamsburg, and there it stayed for decades on end. He never stopped pushing everyone to be careful of Shatnez. He also never stopped making his own signs: 

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 ‘Laboratory’ is a pretty fancy name when compared to the reality. It was really just a messy apartment.  

I went there to take the course in Shatnez testing in 1975. Even though most of my training was from a younger fellow, I got to spend some time with Reb Yosef Rosenberger. 

His part of the training was Musar or ethics. He stressed that every Shatnez tester must recite Psalms, and must learn books of Musar (Jewish ethics) for at least an hour each, every day. I didn’t remain an official tester very long. 

I was truly impressed with his devotion to this cause, and he succeeded. Shatnez testing became very well-known and common by the 70’s. Eventually, large organizations got into the business, like the Star-K, and there are hundreds of labs worldwide. Today, the chemical test is rarely used. Instead, the testers use microscopes to identify the fibers.  

There was a charm and passion to Reb Yosef Rosenberger, who had an Old-World flair about him. But he was determined, and dedicated his life to the observance of this mitzva.  

His will left the following instructions: Because I was so involved in serving the Jewish Public and teaching about Shatnes, it left me with little time for myself to study Torah…in my humble opinion, I think that the same Jewish Public can make this up to me by studying Mishnayos or saying Tehillim on the day of my Yahrzeit (Mar Cheshvon 7. 1996, Yosef ben Moshe Halevy, he left no family).   

He instructed us about an ignored mitzva, and he taught us what one dedicated individual can do: The Power of One!   

Next: Eating Out! 

About the Author
Born in Malden, MA, 1950. Graduate of YU, taught for Rabbi Riskin in Riverdale, NY, and then for 18 years in Efrat with R. Riskin and R. Brovender at Yeshivat Hamivtar. Spent 16 years as Educational Director, Cong. Agudath Sholom, Stamford, CT. Now teach at OU Center and Yeshivat Orayta.
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