Marit ayin (or maris ayin, Hebrew: מַרְאִית עַיִן, "appearance to the eye"), is a concept in halakha (Jewish law) which states that certain actions which might seem to other surrounding people as to be in violation with Jewish law, when in reality they are fully permissible, are themselves not allowed due to rabbinic enactments that were put into place to prevent surrounding onlookers from arriving at a false conclusion. For example, according to the Torah law, the blood of an animal is forbidden to eat, but the blood of a fish is permissible. However, according to the principle of marit ayin, it is forbidden to eat the blood of fish as an onlooker may believe the blood being eaten is from an animal and is thus allowed to be eaten.
There is a disagreement in the Talmud as to whether the concept of marit ayin applies in private. Beit Shamai believes that marit ayin applies even in private, whereas Beit Hillel believes that marit ayin does not apply in private.
Doesn’t always apply
According to Rabbi Moshe Feinstein in his book Igrot Moshe, marit ayin applies only when "Someone thinks that I violated something, or he thinks that I inappropriately ate something non-kosher. However, it does not include doing something permitted that people may mistakenly think is forbidden due to the fact that they do not know the Jewish law." Therefore, a permitted act which an onlooker might come to believe is a forbidden act being performed, is a case of marit ayin and thus not allowed. However, an act which is allowed which an onlooker might believe is forbidden is not case of marit ayin.
Judge your fellow favorably
There is a principal in Judaism called "dan l'kaf zechus" or judge your fellow favorably. The principle of marit ayin seems to be in contradiction with this principle as if one is performing an action that may look forbidden, it shouldn’t be worried that an onlooker will think a forbidden action is being performed as we should judge him favorably that he will judge his fellow individual favorably that he is indeed not performing a wrongful act. However, the truth is that the rabbinic prohibition was not put into place because one may think his fellow man is committing a sin, but rather because he may mistakenly think that the action that he wrongly sees taking place is indeed permissible and thus commits the wrongful action himself in error.
Changes over time
According to the Shulchan Aruch, something which was prohibited in the times of the Talmud because of marit ayin, for which marit ayin for that situation is no longer a concern due to modern day circumstances, the prohibition is cancelled. For example, in the times of the Talmud having soy milk, or non-dairy creamer, during the same meal as meat would have been prohibited because it was likely to think that the person was in violation of the laws of kosher. However, since it is well known today that people use non-dairy creamer, there is no issue of marit ayin, and the prohibition is cancelled.
- Minchas Shlomo 2-3:53.
- Talmud Keritut Pg. 21
- Talmud Beitzah Pg. 9
- Igros Moshe O.C. 1:96.
- Talmud Shavuot Pg. 30
- Igros Moshe O.C. Pg. 243:2