To whom do they say this?
Rashi: To the Tzadikim.
Radak: Those who eat everything Tamei are Temei'im; they say this to Tehorim. Malbim - those who are Metamei themselves covertly say so to the rest of the nation.
Why do they say "Kerav Elecha Al Tigash Bi"?
Rashi: Stand by yourself; do not touch me.
Malbim: Stay in Your border; do not enter my border.
What is the meaning of "Ki Kidashticha"?
Rashi citing Targum Yonasan: I sanctified and purified myself more than you did.
Malbim: If you will touch me, you will become Kadosh. They establish themselves to be so holy that anything that touches them becomes Kadosh, like "Kol ha'Noge'a ba'Mizbe'ach Yikdash" (Shemos 29:37). They consider everyone else Tamei compared to themselves, so others may not touch them, like [a Tamei] may not touch Kodesh.
What is smoke in Hashem's nose?
Rashi: The abominations that they did are smoke of anger in His nose.
Radak: Those who did these evil acts and did not recognize that they did evil, they raise smoke in His nose.
Malbim: These imposters who establish themselves to be holy.
What fire burns the entire day?
Radak: There is fire in My nose the entire day against them and their seed after them. Therefore, I will make the Galus long for their children.
Malbim: It is fire from their sins.
