So, in regard to canonical impediments to Holy Orders (Can. 1040-1049), do these invalidate the sacrament (thus making the receiving person unordained and not possessing of the presbyteral/diaconal/episcopal state) or do they simply make the ordination illicit (thus meaning the priest was prohibited from public ministry like a priest who obtains a dispensation)?
Also, how do some of those, like the impediment against those who attempted suicide (Can. 1041 s. 5), work theologically? Does that particular person’s vocation disappear when they sinned in that way? Did that vocation remain non-existant even after absolution?
None of the impediments listed there are considered to be capable of invalidating ordination. The distinction between an “irregularity” in c. 1041 and “simply impeded” in c. 1042 is present because the simple impediments can cease with time and do not always need a dispensation. So, what can invalidate an ordination? The candidate is not baptized, the candidate never had an intention of receiving ordination, the bishop/candidate was forced into the ordination, the bishop is not really a bishop, or the form of the sacrament was not observed. That’s about it, although there might be something I’m forgetting.
The law is very “liberal” in regard to what it takes for a valid ordination. This is the case since having a lot of invalidating barriers could lead to a certain man performing many sacraments which would, in fact, be invalid because he was never truly ordained. That would be very bad (although God is merciful so he wouldn’t hold it against those who thought they were receiving sacraments).
The presence or absence of an impediment does not mean anything, necessarily, about the presence or lack of a true vocation.