“The lesson to be learned from the story is, that when we see a Jewish woman who is going in clothing which are not Tznius, the immediate reaction is to stand up against it” – The Rebbe, explaining how a person must behave when faced with a woman who does not dress in a Tznius fashion ● Full Story
On Shabbos Shuva, Parshas Ha’azinu 5730, the Rebbe discussed Rav Adda bar Ahava, one of the sages of the Talmud, telling a story about him, and teaching the lesson to be learned from it (Free Translation):
In Tractate Berachos (20a) the Gemara relates: “There was the case of Rav Adda bar Ahava who saw a woman [he thought she was Jewish] wearing a red head-dress [which is Non-Tznius] in the street, and thinking that she was a Jewish woman, he immediately went over and tore it from her.”
The immediate lesson to be learned from the story is, that when we see a Jewish woman who is going in clothing which are not Tznius, the immediate reaction is to stand up against it -not like the people who claim that Tznius is only a Hiddur which doesn’t apply in certain places or certain generations- like we see from Rav Adda bar Ahava who immediately stood up against it; despite him being in exile during a time when Jews were fearful of the Non-Jews – he did not care about that, and took a stand.
The Gemara continues, that afterwards “It turned out that she was a Non-Jewish woman, and they fined him four hundred zuz. He said to her: What is your name. She replied: Mathun. Mathun, he said to her: that makes four hundred zuz.” The word “Mathun” in Hebrew means ‘deliberate,’ had he been less rash he would have saved himself 400 zuz, but we see that he was quick and didn’t wait a moment before doing what needed to be done.
Sichos Kodesh 5730 Vol. 1 page 59