262. I Didn’t Say “Simon Says!”: The prohibition against copying other nations' ways
Do not follow the practices of the nation… (Leviticus 20:23)
Said in reference to the nation of Emor, but equally true of all other nations, God has prohibited us from abandoning our practices in favor of those of another nation. This is why Jews around the world have styles different from those of their non-Jewish neighbors. (Yes, the Jewish communities may often have looks radically different from one another, but they are all still distinctively Jewish.)
The Midrash warns against copying the other nations in terms of fashion (Sifre Deuteronomy 81), as does the prophet Zephaniah in the book that bears his name (“I will punish… all who wear foreign clothes” – Zephaniah 1:8).
The reason for this mitzvah is to distance us somewhat from the other nations, among whom we live. If we differentiate ourselves in matters of dress, we are less likely to copy idolatrous practices or other culturally-accepted behaviors that are counter to the Torah’s ways.
This mitzvah applies to both men and women in all times and places. It is discussed in the Talmud in tractate Shabbos on pages 67a-b. It is codified in the Shulchan Aruch in Yoreh Deah 178. It is #30 of the 365 negative mitzvos in the Rambam’s Sefer HaMitzvos and #21 of the 194 negative mitzvos that can be fulfilled today in the Chofetz Chaim’s Sefer HaMitzvos HaKatzar.