Malbim: Hashem always puts the cure before the illness. The purpose of the affliction is not to afflict, rather, to make them repent, and when they repent, He heals them. This refers to one who sins due to desire. This generation is different. They will get an illness without a cure, for they made a Kesher (rebellion) and chose other gods; they will not repent. If Hashem brings afflictions, they will attribute it to not serving idolatry [enough]. If "they will scream to Me and I will not hear them", they will attribute that the idolatry punished them for not serving it properly. ¹