Popes can err if they are not making proclamations in the limited circumstances in which we believe papal infallibility applies to them, per the 1870 dogma. The pope is not some kind of inspired ...
St. Paul rebuked St. Peter for hypocrisy. Many non-Catholics claim that this proves that Peter wasn’t infallible, and that Paul had at least equal authority (thus, it is regarded as a disproof of the ...