The fourth of the four asmakhtah mishnayot, with four topics within the one mishnah: polatet shikhvat zera, bathing an infant who has undergone brit milah on Shabbat, separation of husband and wife, anointing on Yom Kippur. Which leads into a discussion of the separation between husbands and wives during the giving of the Torah. Via hints of non-legal verses from Tanakh. Also, how the Gemara delves into the first category at length, and why that feels prurient. Plus: separation between husbands and wives at Mount Sinai - when, exactly, did that begin? How, exactly, did they handle it? Also: the importance of careful reading of the entirety of Torah.