1)
Why does it mention Yehudah and Yerushalayim?
1.
Rashi: The Beis ha'Mikdash is there.
2)
What are "ki'Ymei Olam uch'Shanim Kadmoniyos"?
1.
Sifra Shemini Mechilta d'Milu'im 31 #1: They are the days of Moshe and the days of Shlomo, respectively. Malbim - then fire descended from Shamayim and consumed the Olah - so it will be in the future!
2.
Sifra Shemini Mechilta d'Milu'im 31 #2: They are the days of Noach and the days of Hevel, when there was no idolatry in the world. Malbim - also in the future, "Yihyeh Hashem Echad u'Shemo Echad" (Zecharyah 14:9).
