1)
Why does it say "Al Nekalah"?
1.
Rashi: It is easy for them to lie and say that there will be Shalom. Via this, they 'heal 1 ' the destruction that will come upon them.
2.
Radak: Via light words with no substance.
3.
Malbim: They should have healed this mortal disease. The cure is difficult; it is not via mere words!
4.
Refer to 8:11:2:2.
1
I.e. they make them think that they need not be concerned for it. (PF)
2)
Why does it say "Shalom Shalom v'Ein Shalom"?
1.
Radak: They say that there will be Shalom, but there is not Shalom - the enemy comes [closer] every day.
2.
Malbim: They say that the body is healthy; really, it is broken!