What if an adult has committed actual mortal sins prior to Baptism, and at the time of Baptism, he has neither imperfect, nor perfect contrition? There are only two possibilities, either the Sacrament is valid and all sins are forgiven, or the Sacrament is not valid.
If the adult accepts the Sacrament of Baptism willingly, then his willingness to receive the Sacrament is a type of implicit perfect contrition. For Baptism is the foundation of the whole Faith, and by accepting Baptism, the person implicitly accepts all that is of the Faith, including repentance from sin. Although perfect contrition, to be truly perfect, must also include the desire for Confession, in this case, the explicit desire for Baptism substitutes for the desire for Confession, since Baptism forgives sins even more thoroughly than Confession. Therefore, the adult who willingly receives Baptism is forgiven for all his sins, including any actual mortal sins from which he has not explicitly repented, and all venial sins, and all punishment due for all sin, and also he is cleansed of original sin.
If the adult receives the Sacrament of Baptism unwillingly, if either it is forced upon him, or if he has no sincere intention to receive a Sacrament (but perhaps just to attend a ceremony to please a friend or loved one), then he does not receive the Sacrament validly. For every Sacrament requires he who dispenses the Sacrament to intend to do what the Church does. But when a Sacrament requires the participation of an adult, such as in Marriage, or in Confession, the recipient of the Sacrament must also intend to do what the Church does. A couple who do not intend to bind themselves in a lifelong commitment, in a marriage as a Sacrament, not merely as a human custom, do not receive the Sacrament validly. A man who goes to Confession unrepentant does not receive the Sacrament validly, for he does not intend to do what the Church does: contrition and Confession. Thus, an adult who accepts the water of Baptism without intending to do what the Church does, in that he is insincere and does not truly consent to the Sacrament, does not receive Baptism validly, and he is not forgiven.
These are the only two possibilities for the Sacrament of Baptism, either it is valid and all sins are forgiven without exception, or it is not valid and no sins are forgiven.
Some theologians have tried to construct a third possibility, whereby the Baptism is not effective, if the person is in a state of mortal sin, until he subsequently repents and goes to Confession. But this approach undermines and essentially nullifies the ancient and unchanging teaching of the Church that Baptism forgives all sins. For it is claimed that the person’s sins are not forgiven, until he subsequently goes to Confession. But under this approach, the sins are forgiven by Confession, not by Baptism. So Baptism becomes dependent on Confession. And this approach also undermines the teaching that only the Baptized may receive the other Sacraments, including Confession. Therefore, this theological claim is not correct.
[This article is an excerpt from my book: The Catechism of Catholic Ethics, chapter 30, Grace and Salvation.]
Ronald L. Conte Jr.
Roman Catholic theologian and Bible translator