Impervious means: unaffected by, untouched by, immune to, invulnerable to, insusceptible to, resistant to, indifferent to, heedless of, insensible to, "he seemed impervious to the chill wind", impervious to insults, impervious to fear
Of course no one is impervious to anything really, or they would be dead... You need to be present and notice attacks, malicious intention, fear, pain, and everything that you need to protect yourself from.
The impervious we are talking about is the emotional unshakeability that spares you from a life of a roller coaster, from being reactive, from being judgmental, for going into despair or going to mania.
Often anything can kick you into the horizontal plane 1 . I got kicked into it... and now I am working my way off... it is not that easy. I can't even connect to muscle test... the horizontal plane is sticky. It wants you, all of you. I eats your life for breakfast.
Let me explain: Humanity (you!) lives on the horizontal plane at this stage of evolution. It is both the starting point and the end state...
On the horizontal plane everything is about comparison. More, better, different...
This is a good question to chew on, observe, test out, for a True Empath.
The fate of humanity, and your personal well-being, evolution, raising your vibration, depends on your relationship to perfection.
How? Perfection is imposed. Perfection comes from your relationship with something outside of yourself. It's a comparison, and you live in a constant fear of "falling from grace", falling short of perfection. The rules are set by others with an agenda. The agenda isn't overt: in fact, it is a manipulative agenda. The goal is to keep you out of balance, keep you failing, keep you suppressed, keep you small and dependent. 1
Integrity is an inside job. It is between you and you. No one, outside of you, can judge your integrity. Of course, the way the word is used in everyday language makes it, for you, while you are unconscious, part of the perfection racket, but the "real" meaning of integrity is that you act consistent with YOUR interest, with YOUR values, with YOUR Self.
Integrity is an empowering concept, while perfection is disempowering. Integrity has no front office and back office, not shenanigans in the background, it is the same through and through.
While perfection is a Trojan horse. Once it is sneaked into you, you are a puppet on a string, at the mercy of the hidden agenda: you are an effect, never able to succeed in the impossible task of being "sinless". No one is. Your so-called saints are fakes and pretenders.