It seems that a huge number of possible impediments can invalidate a Catholic marriage and make it non-sacramental.
Reading some conservative theologians on Confession (I’m thinking of St Leonard of Port Maurice in particular) making a ‘good’ i.e. valid confession is equally difficult, i.e. the majority of confessions are invalidated by some forgotten or concealed mortal sin, some lack of repentance, or continued attachment to one sin or another.
I understand that the Blessed Sacrament is less complicated, because the subject of the sacrament is bread and wine, which are less likely to be improperly disposed than human souls (unless for some reason they are not really bread or wine). All the same, if my confession or my baptism was not valid, then I am receiving in a state of mortal sin, and thus committing mortal sin. If I am married invalidly, then I am committing a sin with the woman I think is my wife, a sin which I am not confessing, thus invalidating the other sins remitted through absolution, and thus receiving in a state of mortal sin, and thus committing mortal sin… and so on.
If Holy Orders are as easily invalidated as a marriage, i.e. a priest has ‘psychological factors’ putting his intentions into question, then that makes all the other sacraments questionable, does it not?
The sacraments are from Heaven, and we can never perform or receive them with the perfection that they represent. Does that mean that in fact we are on incredibly shaky ground putting our faith in anything the Church does? If all the sacraments can be as easily called into question and nullified under close scrutiny as most Catholic marriages can, does that make them all pretty shaky?
If I am Confirmed with some ‘psychological reservations’ and subsequently apostasise, couldn’t I argue that the absence of the fruit of the sacrament showed I hadn’t been validly Confirmed, and have my Confirmation or even my Baptism anulled and start again with a re-Confirmation or re-Baptism?