When is it wrong (to think that a pope’s teaching is or leads to evil)?
(What time is it …) NOW! (?)
When? NOW! It is wrong to think that a Pope’s teaching is, or leads to, evil (IF that teaching is in the realm of faith or morals) because his office is invested with the
charism of infallibility in those cases.
The office has the keys promised to Peter to bind and loose on Earth, and the same would be held in heaven.
Once the Pope speaks his teaching will not be evil nor lead to it.
One might think his teaching is not as complete as it could be perhaps - and reason that
what he is teaching is “for now” with more to come (say). But not that what he teaches is evil or will lead to evil (of his own or by the Church).
Reasoning that people will rebel against a tough teaching and cause evil is another matter.