What sort of distinction is the Torah warning about?
Rashi: A distinction between slaughtering the majority of the Simanim of an animal (which renders the Shechitah Kosher) and a bird and slaughtering a half (which does not). 1
Targum Onkelos and Targum Yonasan: A distinction between Kasher species of animals and birds and non-Kasher ones.
Rashi: The difference between them is a hair's-breadth. Otherwise, a warning to draw a distinction would be superfluous.
What is the Torah referring to when it adds "v'Lo Seshaktzu es Nafshoseichem ... "?
Seforno: It means that one should not abominate oneself by eating 1 of the species that the Torah has prohibited.
Targum Yonasan: It is referring specifically animals and birds that have ben clawed by a wild beast or by a bird of prey.
Seforno: Specifically eating - which contaminate the soul - but not merely touching (which renders only the body Tamei). Presumably, that is what Rashi means when he comments on "le'Tamei" - 'Le'esor', though unlike the Seforno, he translates "le'Tamei" literally.
'u've'Chol asher Tirmos ha'Adamah" incorporate"?
Rashi (in Makos 16b): It incorporates all animals, beasts and birds
Rashi (Ibid.): Which are not subject to the specific Isur in this Pasuk, because they fall under the category of 'Sheretz' and not that of 'Remes' - See Rashi, Makos, 16b DH 'Rzara'as Lokeh Sheish'.
Why does the Pasuk begin with Achilah ("ve'Lo Seshaktzu es Nafsshooseichem") and then switch to Tum'ah?
Me'ilah, 16b: To teach us that just as the Shi'ur for Tum'as Sheratzim is a k'Adashah 1 (the size of a lentil), so too is the Shi'ur Achilah
The verse mentions distinguishing "between the Tahor and Tamei animals", and "between the Tamei and Tahor birds." Why did it switch the order?
RS"R Hirsh: Whenever the Torah obligates distinguishing, we must ensure that the two kinds not mix. One may not be Metaher the Tamei or Metamei the Tahor, or to forbid the permitted (Yerushalmi Terumos Sof Perek 5). Also above (11:47), it switches the order like this.
Ha'Emek Davar: It mentions first what the Torah listed, i.e. the Tahor animals and the Tamei birds.
Torah Temimah: Because there are more species of Tahor animals than Tamei ones but more species of Tahor birds than Tamei ones. Therefore, the Torah precedes the Tahor species of animals, and the Tamei species of birds - since one tends to separate the minority from the majority. 1
As the Gemara points out in Chulin, 63b
