I remember once I met an Orthodox guy who was a nudist. He loved to lie out naked in the sun. He was caught a few times and got into trouble with his religious community.
It was all so weird to me. I can’t think of anything more opposite than public nudism and Orthodox Judaism.
Rabbi Gil Student posts: The Torah says “??? ???? ?? ???? ??? – He may see no naked thing among you” (Deut. 23:15). The Gemara (Shabbos 150a) learns from the word davar that no dibur (word) of holiness can be recited in front of nakedness. That means no prayer, Shema or words of Torah can be recited in front of someone improperly dressed.
This should effectively prohibit praying on the NYC subway during the summer, when the trains are full of immodestly dressed women. Sleeveless and low-cut shirts, short skirts and shorts, etc. Even closing your eyes is insufficient. The Shulchan Arukh (Orach Chaim 75:6) allows you to close your eyes and then pray but the commentaries (e.g. Magen Avraham 9; Taz 2) require you to turn your back.