What are "Rabos Ra'os"?
Rashi: They are evils or fears. Radak - often Hashem tests a Tzadik for his benefit, and to show his virtue to people, that his heart will not falter and he will not veer from the true path due to afflictions.
Malbim: Illnesses due to a malfunction of one of the foundations of the body, they have no cure. All the pains have one source - the primary vital limb that malfunctioned. However, problems due to an external part of the body, even if they are many, e.g. the skin is damaged in many places, they are not dangerous. The many maladies of a Tzadik are not dangerous, for "Hashem guards his bones" (verse 21), i.e. the pillars of the body.
In what sense is he saved?
Radak: He does not stumble in any [test] - "Ki Sheva Yipol Tzadik v'Kam u'Resha'im Yikashlu v'Ra'ah" (Mishlei 24:16).
