1)
What is "he'Chatzer ha'Chadashah"?
1.
Redak: Perhaps it needed to be strengthened, and they strengthened it.
2.
Radak citing Pesachim 92a: They enacted new matters, and said that a Tevul Yom (one who immersed from Tum'ah today) may not enter Machaneh Levi. I.e. this was not Torah law; they were Mechadesh it.
