“Shaatnez” – a negative commandment, or prohibition of the Torah, against wearing the combination of wool and linen. The Biblical sources of the prohibition are VaYikra (Leviticus) 19:19, where we find, “You shall observe My decrees. You shall not mate your animal with another species, you shall not plant your field with mixed seed; and a garment that contains an interweaving of fibers shall not come upon you.” In Devarim (Deuteronomy) 22:11, the Torah is more specific, “You shall not wear interwoven fibers, wool and linen together.”

Adding to the mystery of “Shaatnez” is that the vestments of the High Priest were made specifically from wool and linen! In addition, “Tzitzis” can be made from wool and linen.

There are two kinds of Torah laws: “Chukim” (decrees) and “Mishpatim” (classic property and damage laws). The latter, which must be obeyed by Jews because they are of Divine origin, still have an obvious logic of their own. Examples are commandments not to steal from one’s neighbor and to return lost property. “Chukim” are Torah laws where the logic is less readily apparent. “Shaatnez” belongs to this classification. Another large category that belongs in this group are the Laws of “Kashrut,” the Jewish Dietary Laws. While those may very well have health and other logical associations, they must be obeyed strictly because the Torah and its Author so commands the Jew.

Again, “Chukim” are commands of the Torah that are obeyed primarily as an act of faith. In fact, however, the logic of “Shaatnez” is not that difficult to discern. It is perhaps easier to see in the context of the Torah prohibitions of inter-breeding species of animals and species of plants. These are, in a way, somewhat of an insult to the Creator, Who created Heaven and Earth with incredible complexity and beauty, and the human being has the “chutzpah” to say, “It’s not good enough – I think changes are necessary.”

“Shaatnez” only applies to wool and linen, the extremes of the fiber spectrum. Wool, the warmest of natural fibers, comes from the animal world; linen, derived from flax, a member of the plant world, is the coolest.

In practical terms, the Jew is allowed to benefit from the inter-breeding of species of animals and plants; he or she is prohibited only from the actual inter-breeding. In the fiber world, the Jew is permitted to blend all fibers, but is prohibited to wear interwoven wool and linen.

“Shaatnez” is most likely to be found in men’s and women’s suits and sportcoats, raincoats and winter coats, among other garments. The first place to look is the label which states what the garment is made of (“lana/lino” means “wool and linen” in Spanish, but does not always appear in garments made in Latin-American countries). Even if examination of the garment’s label does not indicate a problem, certain items, especially those in the list cited above, should be checked at “Shaatnez” – Inspection Services, available in many communities (Consult your local Orthodox Rabbi for directions in your area).

The lifestyle of the Jew is defined by many aspects of behavior: how he or she interacts with their fellow human beings and with G-d, how and what they eat, what they say (marked by the exclusion of untruths and profanity), and how they dress, emphasizing modesty and the more subtle aspect of “Shaatnez.”