There is a useful, well-worn framework for reflecting on sacramental actions – the church’s efficacious signs:
We talk about a sacramental action as licit if it follows the church’s agreements. In the wider church (the church catholic, if you will) sacramental actions are regularly described as having agreed matter and agreed form.
The matter for baptism, for example, is immersion in or pouring of water. The form is the words “I baptise you in the Name of the Father, and of the Son, and of the Holy Spirit”.
Beyond the near-universal agreement on matter and form for a sacramental action, churches have internal agreements about the service within which a sacramental action takes place. The church in which I serve, for example, has a laid out, agreed baptism rite – the words required to be used in that rite go well beyond the form, but the rite includes the form, and indicates the matter. This rite is the licit one to use to baptise in this church.
For a sacramental action to be valid, as well as right matter and form, one needs proper intention. A wedding in a play, as just one example, does not validly marry the actors. The intention is expressed in that context – a play. Obviously we cannot have access to the inner, mental attitude of those involved and leading sacramental action. Normally the rite expresses the intention. For validity, the proper minister is needed to lead the sacramental action. It is normally understood, for example, that a person who is not ordained cannot ordain.
It is possible for a sacramental action to be not licit but yet still valid. A Roman Catholic priest, for example, baptising using an Anglican baptism rite (or vice versa) would not be licit – that is not the agreed rite of that church. But the baptism would still be valid – the person would be validly baptised. Because the matter, form, minister, and intention would still have been as the universal church understands them.
The appropriate recipient of a sacramental action also comes into discussion. We might use the appropriate matter, form, intention, and be the appropriate minister to baptise but, however hard we try, doing this to, say, a rock, does not result in a validly baptised rock.
We can go through sacramental actions – but does it actually make any difference? It is possible to receive communion, for example, with the communion being valid and licit, and yet it make little to no difference to one’s life. In the case of receiving communion, to continue with that example, we, for whom it does make a difference, feed on Christ in our heart by faith with thanksgiving. Yes, it is possible to receive communion and not be nourished by Christ and Christ’s life.
It is normally understood that, in some sacramental actions, the efficacy does not depend on the recipient. The statement ex opere operato (Latin for “by the very fact of the action’s being performed”) refers to God’s faithfulness to God’s promise to work through these signs. Baptism, as just one example, does not depend on the personal holiness of the one administering that sacrament; it also does not depend on the disposition of the recipient. If someone has been baptised validly, it is unacceptable to baptise that person again because the action is God’s.
The other side of the coin is that the fruit of sacramental actions is not independent of the minister of the sacramental action or the recipient. The one leading a service can make a difference to the fruitfulness of those involved in the sacramental action, for example. And the disposition of those receiving communion affects the results in their lives. This has been referred to as ex opere operantis (“from the work of the doer”).
As explained above, if a baptism is valid it cannot be repeated. In the case where a sacramental action is required, and there is uncertainty whether it has been validly done in the past, the sacramental action can be done conditionally. One can baptise, for example, conditionally (sub conditione).
Once we have this framework we can be clearer in discussions that separate Christians. I am not wanting us to attempt to answer these disputed questions, or even discuss them. I am merely showing how the framework enables such discussions to be clear. Questions such as:
Can grape juice be used as matter for communion?
Are presbyters proper ministers to ordain?
Can water poured be used as the matter for baptism?
Is a baby the appropriate recipient for baptism?
Can a person living with unrepented sin be validly ordained?