In the past, sha’atnez was often readily identifiable, since most threads and fabrics were made of wool or linen and many people knew how to distinguish them. Some garments were so obviously sha’atnez that, within the Jewish community, any Jew who wore them was understood to be openly defying Jewish practice and desecrating God’s name. Other garments were known by most Jews to contain sha’atnez, although not everyone could recognize it, while still others could be identified only by experts. A person might therefore buy and put on a garment, only to discover while standing in the marketplace that he was wearing sha’atnez prohibited by Torah law. He must then remove it immediately, even if this leaves him naked and humiliated in the street, for “there is no understanding and no counsel against the Lord”: wherever God’s name is desecrated, honor is not accorded even to a rabbi (Berakhot 19b; SA YD 303:1).
If he refuses to remove the garment because he is embarrassed, some authorities maintain that the mitzva of rebuke and the mutual responsibility shared by all Jews require another Jew to tear the garment off him (Rambam; SA YD 303:1). This applies only when the wearer accepts the halakha but finds it difficult to comply; in such a case, it may be assumed that he will ultimately be grateful to the person who tore off the garment and prevented him from violating the prohibition. If, however, he has cast off the yoke of the mitzvot, tearing off the garment will not bring him closer to Torah and mitzvot and should not be done. Many authorities maintain that even when the wearer accepts the halakha in principle, one should rebuke him but may not tear the garment from him (Rosh; Rashba; Ra’ah; Terumat Ha-deshen).
The authorities disagree about what one should do upon seeing someone unknowingly wearing a sha’atnez garment when removing it immediately would cause him severe embarrassment. Many maintain that one should not inform him on the spot, since doing so would force him to undress publicly. Instead, one should invite him home and tell him there that the garment contains sha’atnez (Rosh; Terumat Ha-deshen; Rema). Others maintain that he must be informed immediately so that he can remove the garment without delay (Rambam; Radbaz).[9]
According to Rambam, one who sees another person – even his teacher – wearing kilayim prohibited by Torah law must “rush over and tear the garment off him immediately” (MT, Laws of Kilayim 10:29). This ruling is based on Rambam’s version of the Gemara. Radbaz and Kesef Mishneh explain that Rambam understood the incident involving Rav Adda b. Ahava accordingly: he tore a woman’s garment because he mistakenly believed that she was Jewish and was wearing kilayim prohibited by Torah law (Berakhot 20a). This is also the ruling of SA YD 303:1 and Sha’agat Aryeh §58.
Rosh, however, understands Berakhot 19b differently. If one sees another person deliberately wearing kilayim, he must rebuke him, even though compliance will require the wearer to remove the garment in public and suffer embarrassment. Rosh makes no mention of tearing the garment. If the person put on the sha’atnez unknowingly, however, one should not inform him until he reaches home, so that he will not be humiliated by having to remove it in public. Rosh derives this distinction from the Yerushalmi. This is also the view of Terumat Ha-deshen, Rema, Rash Sirilio, Baḥ – who maintains that Rambam agrees – and Peri Yitzḥak 1:26.
Other Rishonim explain that the Gemara discusses a person who suddenly discovers kilayim in his own garment and is therefore required to remove it. It does not address whether someone else must inform an unaware wearer when doing so will cause him public embarrassment (Rashba; Ra’ah; Orḥot Ḥayim; Meiri). It appears that these authorities agree in practice with Rosh, since they too recognize the obligation to rebuke another person in accordance with the laws governing rebuke. In any event, none of the authorities who disagree with Rambam suggest tearing another person’s garment in order to save him from the prohibition; their discussion concerns rebuke alone.
