Kelim, Chapter Twenty-Seven, Mishnah Ten
1) If a piece of cloth three [handbreadths] square was divided, it is pure from midras uncleanness but is still unclean from contact with midras uncleanness.
2) Rabbi Yose said: but what midras uncleanness has this touched!
a) Only if a zav had touched it is it unclean from contact with a zav.
Section one: In order for the piece of cloth to be susceptible to midras uncleanness, it must be three handbreadths square, as we learned in mishnah two. If it is divided in half, each piece can no longer be unclean with midras, but each piece had “contact with itself.” Therefore, both pieces retain uncleanness by virtue of contact with midras.
Section two: Rabbi Yose’s words here are exactly the same as in yesterday’s mishnah. Again he holds that impurity is not conveyed by “contact with itself.” Therefore, if the two halves of the piece of cloth do not have midras uncleanness, they also do not have uncleanness by contact with midras. Nevertheless, if a zav had actually touched the cloth, it retains the uncleanness contracted through contact with a zav. Such uncleanness is not lost when the cloth becomes less than three handbreadths square, as long as it is at least three fingerbreadths square.