What is "ve'Zos" coming to include (See Torah Temimah, note 8)?
Nidah, 55b: It comes to incorporate the Zav's urine in the Din of Zivus. 1
Why does the Torah insert the (otherwise superlfuous) word "ve'Zos Tih'yeh Tum'aso be'Zovo"?
What are the implications of the words "Tum'aso be'Zovo"?
Bava Kama, 24a: It implies that, as opposed to a Zavah, whose Zivus depends on days, 1 the Zivus of a Zav sepends on sightings
What is the meaning of "Rar"?
Rashi (Shmuel 1, 21:14): It means a fluid that drips - like spit ('Rir') 1 :
See the Pasuk there.
Why does the Torah write both "Rar Besaro es Zovo" and "Hechtim Besaro"?
Rashi: The former means that the emission comes out in the form of a liquid, the latter, even if it comes out thick and stops up the hole of the Amah.
Moshav Zekenim, from R. Nasan (in Nidah 43b): "Hechtim Besaro" teaches that there is a Shi'ur for Zov, i.e. enough to stop up the hole of the Amah. 1
Nidah, 43b "O Hechtim Besaro" teaches us that Zivus is only Metamei as long as it is moist, but not once it has become dry. 2
Oznayim la'Torah: "Rar Besaro" implies long, drawn-out sighting; 3 "Hechtim Besaro", a short sighting
What are the implications of the 'Mem' of "mi'Zovo"?
Nidah, 43b: It implies 'Miktzas Zovo Tamei'
What are the implications of "Tum'aso Hi"?
Sifra: It implies that white Zivus is confined to a man, and the Zivus of a woman is exclusively blood.
Oznayim la'Torah: The Torah writes "Tum'aso hi" rather than 'Tamei hu'
See Oznayim la'Torah DH 've'Zos Tih'yeh ... '.