What sin did the sinner transgress that requires him to bring a Korban?
What did the sinner forget?
How do we know that the current Din also applies to someone who touched the Neveilah of a Tahor animal?
Tosefta Shevu'os, 1:4: From the fact that the Torah inserts "Tamei" by Sheretz, despite the fact that all Sheratzim are Tamei. 1
Bearing in mind that 'Chayah' incorporates Beheimah, why does the Torah insert "O be'Nivlas Beheimah"?
Shevu'os, 7a: To teach us, via a Gezeirah Shavah "Beheimah Teme'ah" "Beheimah Teme'ah" from Tzav, 7:21, that he is Chayav for Tum'as Kodesh ? if he eats Kodshim be'Tum'as ha'Guf. 1
Why does the Torah need to add "O Sheretz Tamei"?
Oznayim la'Torah: To teach us that "Beheimah Teme'ah" and "Chayah Teme'ah" are referring even to animals that are permitted to eat and which became Tamei via Shechitah 1 and not to species of animals that are forbidden to eat ? even if they are Shechted, such as a lion and a bear ? in which case "Teme'ah" means forbidden to eat.
Oznayim la'Torah: Like Sheratzim, which are all forbidden to eat, and which "Tamei" casn only therefore mean literally 'Tamei'.
Why does the Torah add the word "Teme'ah" by Beheimah, by Chayah and by Sheretz?
Sifra: By Beheimah, to teach us that the Din Tum'ah applies even if one touches the horns or the hair (as long as they are attached to the animal); By Chayah, even if he touched a k'Zayis of the Neveilah; and by Sheretz, even if he touched its blood, what is attached to it or its mixture.
Torah Temimah: Because Neveilah is more common by Tamei animals, since Tahor animals are generally Shechted. 1
Why does the Torah specify "Chayah Teme'ah", "Beheimah Teme'ah" and "Sheretz Tamei"?
Sifra: To confine the Din of Tum'as Kodesh and Mikdash to someone who touched an Av ha'Tum'ah (and who is a Rishon), but not to someone who touched a Rishon le'Tum'ah (who is a Sheini).
