2724. Accompaniments of Repentance as to Mortal Sin.—(a) When one mortal sin is forgiven, every other mortal sin is forgiven at the same time. For no one can be truly repentant unless he grieves over his separation from God, and this means that he grieves over each individual mortal sin. But, since venial sin does not separate from God, it is possible to be sorry for one venial sin without being sorry for another.
(b) When mortal sin is forgiven, the eternal punishment is also forgiven, for forgiveness makes man a friend of God and an heir to heaven. But the temporal punishment may remain due, as is proved by the examples of Adam (Gen., iii. 23; Wisd., x. 2), of Mary, the sister of Moses (Num., xii.), of Moses (Num., xx. 12), of David (II Kings, xii. 13, 14), and of others. God is not only a merciful Father, but also a just Ruler, and it is fitting that He should exact satisfaction even for sin forgiven. But if repentance is very perfect like that of Magdalen and St. Paul, even the temporal punishment is forgiven.
2725. The Fruits of Repentance.—(a) Every sin, no matter how grievous, is removed by repentance (Is., i. 18), and hence there is always room for forgiveness. For man is always able to repent and God is always ready to pardon the penitent (Joel, ii. 13). The unpardonable sin is refusal to repent of sin, if one continues in that refusal, but even impenitence is forgiven when laid aside (see 900).
(b) Sin once forgiven does not return, for God does not regret His gifts (Rom, xi. 29), and His pardon means that the guilt of a sin is destroyed and wiped out forever, But he who falls into the same sins after pardon increases his guilt by reason of his ingratitude.
(c) The repentant sinner recovers the infused virtues he lost by sin and also his former merits (Luke, XV. 22; Joel, ii. 25; Ezech., xxxiii. 12; Heb., vi. 10). Virginity of body and innocence of soul are not recovered as to their material elements (i.e., bodily integrity and freedom from all sin), but they are restored as to their formal part, which is the resolve to abstain from all venereal pleasure or to avoid all sin. It seems that former merits are also recovered, not necessarily in their entirety, but in a degree that corresponds with the greater or less excellence of repentance.
2726. Forgiveness of Sin through the Use of the Sacraments.—(a) Mortal sins are forgiven by the Sacraments in virtue of the rite itself (_ex opere operato_) and immediately; that is, the Sacraments either _per se_ or _per accidens_ (according as they are Sacraments of the Dead or Sacraments of the Living) produce in the soul first grace or justification, which is the opposite of mortal sin.
(b) Venial sins are forgiven by the Sacraments in virtue of the rite itself but not immediately; that is, the Sacraments produce directly either first or second grace, and indirectly through this grace they may awaken fervor, which is the opposite of venial sin. The sacramentals, on the contrary, remit venial sins, not in virtue of the rite itself but in virtue of the intercession of the Church attached to the rite (_ex opere operantis Ecclesiae_); for the prayers of the Church are acceptable to God and can obtain from Him a grace of repentance that will remove venial sin.
2727. The Sacrament of Penance.—For those who lose grace after Baptism the Sacrament of Penance is necessary as a part of repentance and a means of forgiveness. This Sacrament may be defined as “a Sacrament of the New Law instituted by Christ in the form of a judicial process, in which, through the absolution of the priest, sins committed after Baptism are forgiven to penitents who confess them with sorrow.”
(a) The remote matter of this Sacrament is the personal sins committed after Baptism, for Baptism washes away all sins committed before its reception. Of this remote matter, some is necessary (i.e., sins that must be confessed), namely, post-baptismal mortal sins not yet declared or directly absolved in confession; some is free (i.e., sins that may, but need not be confessed), namely, post-baptismal mortal sins already forgiven in confession, and post-baptismal venial sins, whether already remitted or not (Canon 902). Imperfections which are not sins, or whose sinfulness is doubtful, are not sufficient matter for absolution; and if they alone are confessed, absolution may not be given, unless there is necessity, and then it may be granted conditionally (see 185, 186).
(b) The proximate matter of this Sacrament, according to the view commonly held, is the three acts of the penitent—contrition in the heart, confession in words, and satisfaction in work. Contrition must exist actually, but the other two acts in case of necessity need not exist actually, but are included implicitly in the act of contrition.