Why does the Torah write "Kedoshim Yih'yu" and not "Kedoshim Heim"?
Rashi: To teach the Beis-Din to force the Kohanim to sanctify themselves in the above regards if necessary, even if they do not want to.
Ramban: Because 'Kedushah' is synonymous with 'P'rishus' (abstinence). 1 The Torah is therefore instructing the Kohanim to abstain from things that are permitted to a Yisrael - such as Tum'as Meis and marrying the women that the Torah forbade.
Refer to 19:2:2:2***.
Why is the word "Heim Makrivim" coming to preclude?
Why does the Torah repeat "Vahu Kodesh"
Sanhedrin, 51b: It order to incorporate Ba'alei Mumin in the realm of Kedushah. 1
See Torah Temimah, note 44, who elaborates.
To which Mitzvos does "Kedoshim Yih'yu" apply?
Moshav Zekenim (on Pasuk 8): It applies to shaving the corners of the beard (in the previous Pasuk), as is clear from Nazir 1 but not to Zonah in the coming Pasuk.
57b. Shi'urei R. Shmuel (Sanhedrin 18b) says that it applies also to Korchah in the same Pasuk (and certainly to Seritah. Yevamos 20a says that there is an Asei of an Almanah Besulah to a Kohen Gadol ("Ishah bi'Vesulehah Yikach") implies that there is no Asei of "Kedoshim Yih'yu." However, the Rashba says that there is.
