"But we are not of those who shrink back and are destroyed..."
Yes, Louise, I am quickly losing patience!
Some are evidently quite able to shrink back (fall away from the faith)
and be destroyed ... and we izn't talkin' about their reputations!!!
Even beyond this, Paul is demonstrating his usual method of ...
(drum roll, please)
MANY MANY MANY MANY edifications, exhortations, encouragemens, etc.
mixed in with a very tasty garlic sauce WITH his dire warnings!
(Jesus taught him over 17 years to do this, even why to do it I'm sure).
Re: your verse above ... Paul is saying with a great hopefull expectation ,
"Surely, boys 'n gals, youse wouldn't be found guilty of this, wouldest thou?"
Now, Jonathan, please try hard to get the drift of this, wouldya?