We are forbidden to cover ourselves with garments which contain both wool and linen. This prohibition, called shatnez, is easy to transgress in a world where we don’t sew our own clothes or even know what’s in the clothing we wear. Clothing labels don’t always list miniscule amounts of fabric, so a garment labeled as made of wool might actually contain linen, and a garment labeled as made of linen could conceivably also have some wool in it. Lined garments, like jackets or coats, often contain shatnez inside the lapels. That’s why it’s important to learn the halacha of when it’s necessary to test and check for shatnez.

This mitzvah is one of the mitzvos that we can’t explain. On the surface, there doesn’t seem to be any reason not to wear a combination of wool and linen. But because of our deep love for Hashem, we are careful to fulfill even the mitzvos whose reasoning is beyond the human intellect.

Laws of Shatnez: What and How to Check

This presentation covers the laws of shatnez, including which items of clothing must be checked, how to check and what they do in a shatnez lab. You’ll also learn about Rav Yosef Rosenberger, an Austrian Holocaust survivor who immigrated to the United States, raised awareness about the mitzvah of shatnez and developed a low-cost way to test for it. He overcame many challenges to change the world through single-minded determination and a love of Torah. He will inspire you to think about how you can change the world.