Imprimatur: An official approval from the hierarchy of the Roman Catholic Church stating that a literary or similar work is totally free from error in all matters of faith and doctrine and hence acceptable reading for faithful Catholics.
Ex Cathedra: Refers to infallible or definitive teachings of the pope as earthly shepherd of the Church.
(Presuming the above are acceptable Catholic definitions).
I understand that when the Pope speaks “Ex Cathedra” he can not teach error in matters of faith and morals. Does the same apply to Imprimatur statements? Could a bishop issue an Imprimatur and be in error when doing so? If so, how can we know for certain that we can trust the Imprimatur?
Could you help me understand the key differences when referring to something that is taught “Ex Cathedra” and something that has an “Imprimatur”?