Kapłańska 21:11 Komentarz: Rashi, Siftei Chakhamim, Chizkuni & Ibn Ezra

'ועל כל נפשת מת וגו‎‎ means, he shall not go into a tent wherein is a corpse.

A tent [which is over a] dead body. I.e., because it is written “he shall not enter,” and entering is not applicable except into something that has an interior.

ועל כל נפשות מת לא יבא, “he shall not go to make contact with any corpse.” This is a warning to the High Priest not to be in the same covered airspace with any corpse. Seeing that this could have been derived already from the previous verse, it is clear that here the Torah includes ordinary priests in this legislation also. The linkage known as g’zeyrah shava, is established by the word יבא which is used here in connection with the High Priest, followed by the unnecessary

נפשת מת — The word נפשת, which appears redundant, is intended to include a quarter of a log of the blood of a corpse — to intimate that even this, as a corpse itself, makes men and vessels unclean through being in a "tent” in which it happens to be (Sanhedrin 4a).

לאביו ולאמו לא יטמא NOR SHALL HE DEFILE HIMSELF FOR HIS FATHER OR FOR HIS MOTHER — By these words which appear redundant, since אביו ואמו are included in כל נפשת מת, Scripture has no other intention than to permit him to defile himself for a מת מצוה (cf. v. 1) (Sifra, Emor, Section 2 4; Nazir 47b).