Niddah 9:2 - 9:3

שעשו צרכיהם – that they urinated.

רבי יוסי מטהר – for even for a woman alone for which there is only one doubt, that is the doubt of whether it (i.e., the blood) comes from the interior of the womb or whether it comes from the place of the urine, Rabbi Yossi declares her pure above (see previous Mishnah), and all the more so if here if it comes from a man. But the Tanna/teacher here does not repeat that Rabbi Yossi declares her pure but rather to teach us from an extraneous Mishnah that even ab initio, Rabbi Yossi declares pure a woman who performed her needs (i.e., urination) and saw blood, that she should occupy herself in purity, and not state specifically that post-facto Rabbi Yossi declares her to maintain her purity that she was engaged with, but ab initio we state that she is not occupied in purity, this comes to teach us that the opposite is true.

ר' שמעון מטמא – even here where there is a compound uncertainty, as the reason is taught.

שחזקת דמים מן האשה – and above (i.e., in the previous Mishnah), we determined that the Halakha is according to Rabbi Yossi who declares her to be pure with one doubt, and all the more so here when there is a compound uncertainty.

השאילה חלוקה – and afterwards she herself wore it and found upon it a bloodstain.

לנכרית או לנדה – to a heathen woman that she sees blood, that she is an adult and we knew about her that she had already seen it (i.e., blood), similar to a menstruating woman/Niddah.

הרי זו תולה בה – but she [herself] is pure. For since she (i.e., the woman who had borrowed it) was a menstruating woman, it did not put her into disarray at all. And a heathen woman also is impure and she receives blame for it. But an Israelite is pure that borrowed a garment from her pure female friend, and afterwards, her friend wore it, both of them are impure, as it is taught [further on in our Mishnah]: three women, etc. for since if she had not blamed it, it would disarray/upset her, for what good is something that upsets this one (i.e., woman) more than that one?

של אבן – that is not susceptible to receive [ritual] impurity. But the bench [that we are speaking of] in the first clause [of the Mishnah] is made of wood and it is appropriate to be defiled through the sitting of a person with gonorrhea or the menstruating woman.

אין מקבל כתמים – meaning to say that they (i.e., the Rabbis) did not make a decree on the bloodstains that are found on it. And the reason of Rabbi Nehemiah, as it is written (Isaiah 3:26): “[And her gates shall lament and mourn,] And she shall be emptied, shall sit on the ground/ונקתה לארץ תשב (see also Lamentations 2:8), since she sat on the ground that is not susceptible to receive [ritual] uncleanness, she shall be emptied/cleaned. And the same law applies to all things that are not susceptible to receive [ritual] uncleanness. And similarly, if she sat in connection with an earthenware utensil, that is not susceptible to receive [ritual] uncleanness from the outside (see Tractate Niddah 60b), or on a patch/strip of cloth that lacks three [handbreadths] by three [handbreadths] that is not susceptible to receive [ritual] uncleanness, in all of these, they (i.e., the Sages) did not decree on bloodstains that are found on them. And the Halakha is according to Rabbi Nehemiah.