I keep reading about shatnez showing up in strange places: ladies sweaters, children’s clothes, and even baseball gloves. Am I required to take my family’s entire wardrobe to a shatnez laboratory to have everything checked?
“What does a shatnez tester look for?”
“The importer told me that the garment was made from a blend of hemp and wool, which should involve no shatnez concern. As there was no authorized shatnez tester in town, I did what I thought was the next-best thing – I brought the garment to a local observant tailor, to have him check it. He carefully checked the threads and guaranteed me that the garment contained no linen. Only after I wore the garment many times did I meet a great Torah scholar and mention this incident in passing. The talmid chacham told me that I should not be so certain, and he offered to compare the material in my garment to linen threads he had available. And indeed, it was clear that he was correct. The threads in my garment were made from wool and linen, not hemp, and I had been violating a Torah prohibition the entire time!”
Does this story sound contemporary and familiar? As a matter of fact, this story happened in 1650 in the city of Vilna — twenty years before the Dutchman van Leeuwenhoek invented the microscope. In those days, the only “scientific” means of checking whether a material was linen or hemp was to take a sample and see if a candle would get it to burn, since hemp is more flammable than linen (Rama, Yoreh Deah 302:2). Others opposed the reliability of this test (Piskei Teshuvah 302:1, quoting Shu”t Penei Yehoshua).
Thus, we see that shatnez problems are not exclusively a result of modern manufacture. However, in modern clothing one may find shatnez in everything from sweaters and skirts to scarves; and from bedding and button loops to baseball gloves.
Before delving into contemporary questions, we must first understand some of the laws taught in this week’s parsha. The prohibition of shatnez exists only if the garment is made from a blend of sheep’s wool and linen, but that wool of other species does not make shatnez. Thus, wool made of camel’s, rabbit’s or goat’s hair mixed with linen is not shatnez (Mishnah, Kilayim 9:1; see Rambam, Hilchos Kilayim 10:2). (“Wool” is simply hair that is soft and can be used as cloth.) The Mishnah (Kilayim 9:2) records that certain combinations, such as silk and wool, were prohibited because of maris ayin, since this raises suspicion or may be misinterpreted that someone is wearing shatnez. However, the Rishonim already conclude that this concern exists only when the material that may be confused with wool or linen is not commonly obtainable, but that no prohibition of maris ayin exists once people become familiar with its availability (Rosh, Hilchos Kilayim).
Most people are surprised to discover that a garment made of a blend of linen and either mohair or cashmere is not shatnez! Why is this? Because neither mohair nor cashmere are made from sheep’s wool, but from the hair of goats! Mohair is processed from the hair of an angora goat. Although goats of this variety are now raised around the world, originally they were developed in Turkey. (The current capital of Turkey, Ankara, used to be called Angora.)
Cashmere is the wool of the Kashmir goat, which was originally native to central Asia, as its name indicates. Thus, if no sheep’s wool thread was mixed into the mohair or the cashmere, the existence of linen in the garment will not make it shatnez.
The Majority Rules
By the way, a garment could contain both linen and sheep’s wool and still not be shatnez! How could this be?
When a thread is spun from a mix of fibers, the halachic status of the thread is determined by what composes most of the thread’s fiber content and ignores the existence of other fibers inside the thread (Mishnah Kilayim 9:1). The minority of fiber is halachically bateil, or nullified, to the majority fiber content in the thread. Thus, threads spun from a mix of mostly cotton fiber with some linen fiber are considered cotton and can be used lichatchilah in a woolen garment. Similarly, a garment consisting of threads made of a blend of mostly mohair but including some sheep’s wool fiber that are woven or sewn with linen threads is not shatnez and may be worn.
Here is a very practical example of this case – in a dress that was tested recently in a shatnez laboratory.
A knit dress whose content label listed 70% wool and 30% silk, which should not be a shatnez problem, was brought to a shatnez checking service. However, the tester noticed that the front panel of the dress was made of thread that was a blend of linen and cotton fibers. If the cotton is the majority, there is no halachic problem with this garment, since this would be considered a cotton thread. However, if the majority component of the threads is linen, the garment is shatnez.
Here is another recent case where the halacha is more complicated:
The label of a sweater brought to a shatnez checking service accurately described its content as: 28% viscose, 20% nylon, 15% lamb’s wool, 15% cotton, 10% polyester, 6% metallic fiber, 3% cashmere and 3% angora. A decorative cloth ornament, whose content was not included on the label, was sewn onto the sweater. The shatnez checker tested the ornament and discovered that it was made of a blend of linen and cotton, where linen was the majority. Thus, the decorative fabric was halachically considered linen, and the material of the main sweater included wool. However, it is possible that there is no shatnez problem here because the wool in the sweater fabric was a minority component. Thus, although there was both linen thread and wool fiber in the garment, it would not be shatnez.
Why did I say only that “it is possible that there is no shatnez problem?”
The authorities dispute whether shatnez exists when there is noticeable wool fiber in a thread which is mostly made from a different fiber. The Rosh (Shu”t 2:5), Mishnah Rishonah and Tiferes Yisrael (both to Kilayim 9:1) consider this shatnez, since the wool is noticeable; whereas the Chazon Ish (Yoreh Deah 181:9) rules that this is not shatnez, contending that the definition of a thread is its majority component, and that the minority wool component of the thread is bateil. In the case at hand, the wool may be noticeable in the thread, since there is a sizable amount of lamb’s wool in a blend that contains many very non-wool type fibers. It may indeed be that according to the Rosh the wool is not bateil in this case, and that this sweater is therefore shatnez. On the other hand, according to the Chazon Ish, since most of the fiber in the thread is not wool, the wool component of the thread is bateil.
Hanging by a Thread
Linen or wool fiber is bateil only as fiber. However, a thread of linen that is woven or otherwise attached into a woolen garment renders the garment shatnez, and there is no bitul (Rosh, Hilchos Kilaei Begadim #5 quoting Tosefta; Shulchan Aruch, Yoreh Deah 299:1). Even a single linen thread in a large woolen garment renders the entire garment shatnez. In addition, if a spun thread is mixed into a larger thread, then there is a shatnez problem min haTorah even if there is only one linen thread in a large garment.
This distinction is extremely important, as we see from the following case:
A 100% pure wool sweater contained a long green thread knotted into its seam. The green thread consisted of a cotton braid, which was not mentioned on the label, but should not present any problem either. However, the core of the cotton braid contained a linen thread. Thus, the 100% pure wool sweater contained a linen thread. (We will soon see that according to many authorities this particular sweater was not shatnez for a different reason.)
What if they do not touch?
If a garment contains wool thread on one side and linen in a different place — so that the wool and linen do not touch, is the garment shatnez?
This issue is disputed by the Rishonim. The Rash (Kilayim 9:1, 9) one of the early Baalei Tosafos, (this is Rabbeinu Shimshon, author of the Tosafos commentary to Zera’im, Taharos, Pesachim and Kesubos, and should not be confused with the more frequently quoted Rosh, Rabbeinu Asher, who also authored commentaries on the Mishnah, Gemara and Halacha, and lived somewhat later than the Rash), rules that shatnez requires that the linen and the wool actually touch, but that one is permitted to wear a garment containing wool and linen threads that are on different parts of the garment. According to the Rash, the prohibition of shatnez is that there is a “combination” of wool and linen, but this is avoided when the wool and linen are separated by other materials.
Based on this Rash, a common custom was to attach a linen atarah to a wool talis by having cotton cloth act as the “mechitzah” between the wool and the linen.
However, the Rambam rules that wool and linen threads on different parts of a garment constitutes shatnez min haTorah. In his opinion, the Torah prohibited a garment containing both wool and linen, even if the linen and wool themselves do not touch. Thus, according to the Rambam, the separating cotton does not change the garment from being shatnez, and wearing the above-mentioned talis is a mitzvah habaah be’aveirah.
Similarly, whether the wool sweater with the cotton green thread containing a core that is a linen thread is shatnez or not is dependent on this dispute between the Rash and the Rambam, since the linen thread does not touch the wool but is surrounded by cotton. According to the Rambam, wearing this sweater involves a Torah prohibition of shatnez, whereas according to the Rash, it is permitted!
How do we rule?
The Shulchan Aruch (Yoreh Deah 299:2) rules like the Rambam that a garment is shatnez even if the wool and the linen threads are separated by other materials. Thus, Sefardim, who follow the Shulchan Aruch’s rulings, are certainly prohibited from wearing this sweater. Among Ashkenazi authorities, the Rosh, the Rama (Yoreh Deah 299:2), the Magen Avraham (9:8) and the Eliyah Rabbah (Orach Chayim 9:6) rule like the Rash, whereas the Mishkenos Yaakov (Yoreh Deah Shu”t #70) Shenos Eliyahu (9:1), Artzos Hachayim rule like the Rambam. I note that Rav Chayim Kanievski notes that the prevalent practice is to rule like the lenient opinion (Derech Emunah, Hilchos Kilayim, Hilchos Kilayim 10:41).
What have we learned so far?
1. We have learned that shatnez exists only when there is sheep’s wool, but not when the wool is from other species, and that therefore pure cashmere or mohair blended with linen is not a shatnez concern.
2. We have also learned that some testing for shatnez existed even before the microscope, but there was halachic controversy concerning whether one could rely that this testing is reliable.
3. In addition, we have learned that threads spun from a mix of cotton and linen fibers are considered cotton and when blended in a woolen garment are not shatnez. However, threads of linen woven into a garment that is a cotton/wool blend is shatnez, even when the blend is mostly cotton thread.
What have we not yet learned?
1. Are baseball gloves a shatnez problem?
2. Which garments must be checked for shatnez.
3. How a shatnez tester works.
To answer these and other shatnez questions, we will need to read a future article.
 We should note that in his notes to Shulchan Aruch (299:8), the Gra, who also authored Shenos Eliyahu, appears to accept the Rash‘s approach.