He was declared a heretic – and yet he didn’t teach a heretical doctrine,so his kind of “heresy” does not contradict the infallibility of the popes as it was defined by Vatican 1. What more do you want?
catholic-legate.com/articles/honorius.html
< As far as the definition of papal infallibility, invoked at the First Vatican Council in 1870, is concerned, it permits a Pope being negligent while on the Papal throne but not, quite obviously, actually pronouncing error from it.
The First Vatican Council taught:
…we teach and define as a divinely revealed dogma that:
when the Roman pontiff speaks EX CATHEDRA, that is, when,
i) in the exercise of his office as shepherd and teacher of all Christians,
ii) in virtue of his supreme apostolic authority,
iii) he defines a doctrine concerning faith or morals to be held by the whole church,
he possesses, by the divine assistance promised to him in blessed Peter, that infallibility which the divine Redeemer willed his church to enjoy in defining doctrine concerning faith or morals. Therefore, such definitions of the Roman pontiff are of themselves, and not by the consent of the church, irreformable.
(Vatican I, On the infallible teaching authority of the Roman pontiff, 4:9)
When we compare the above definition of papal infallibility to Honorius’ statement which we cited earlier, we can see quite clearly that the breach of papal infallibility that Honorius has been alleged to cause is quite ridiculous:
“…on account of the simplicity of man and to avoid controversies, we must, as I have already said, define neither one nor two operations in the mediator between God and man.” (2) “Non nos oportet unam aut duas op operationes predicare”]
In sum, not only has papal infallibility not been breached, but there is no concrete proof that Honorius was, himself, even a formal or material heretic. In fact, the evidence points to the opposite conclusion, even if it must be conceded that Honorius was a negligent Pope. >