2737. Confession.—The second act of the penitent is confession, that is, the declaration of one’s sins made to a duly authorized priest with the purpose of obtaining absolution. Confession is obligatory both from divine and ecclesiastical law.
(a) According to divine law, the forgiveness of grave post-baptismal sins is subject to the power of the keys, which is exercised in the form of a judgment and requires confession (Matt., xviii, 18; John, xx. 23). This law obliges _per se_ in danger of death, and occasionally during life; _per accidens_, when one in sin intends to receive Communion, when one is unable without confession to recover the necessary state of grace or overcome a serious temptation or bad habit.
(b) According to church law, the faithful must go to confession once a year (2590), and confession is also prescribed at times for those who wish to receive Communion (2705) or celebrate Mass (2701 c, 2711).
2738. The Qualities of Confession.—(a) Confession is an act of virtue and should have the conditions of a virtue; that is, it should be discreet (e.g., the penitent should not reveal the names or sins of others), willing, and pure in motive (e.g., the penitent should not confess for temporal ends, such as the good opinion of the confessor), and courageous (i.e., the penitent should not be deterred by shame).
(b) Confession is an act of penitence, and, as penitence includes hatred and regret for sin and abasement of self, confession should not be boastful, jocular or proud, but shamefaced, sorrowful and humble.
(c) Confession is essentially a declaration of fact, and hence it should avoid the defects that make a declaration valueless or imperfect, namely, falsehood, obscurity, digression, or concealment. Confession, then, should be truthful, clear, to the point, and entire.
(d) Confession belongs to the Sacrament of Penance, which is the forum of conscience, and hence the penitent accuses himself, submits to the judgment of the father confessor, and is heard in secret. Public confession is valid but not obligatory. Hence, one who does not speak the language of the confessor is not bound to use an interpreter. Regularly confession should be vocal, but for grave reasons (e.g., if the penitent is dumb, or the confessor is deaf, or there is danger of being heard by those nearby) it may be made by signs or in writing. In case of a written confession the penitent should declare orally, if possible, that the writing contains his confession (see Canon 903).
2739. Is it a Grave Sin to Lie to the Confessor?—(a) There is a grave sin when the lie deceives the confessor about necessary matter (e.g., when a circumstance changing the theological species of a sin is denied), or about free matter which is the only sin confessed (e.g., when a penitent lyingly accuses himself of only one sin and that a venial one), or about free matter which the confessor asks about and needs to know (e.g., about habits or occasions of sin). He who falsely accuses himself of a grave sin, or who exaggerates the number of his grave sins, _per se_ sins mortally; but he is excused if he is ignorant or is under a momentary excitement or delusion. Not only is there grave sin in the cited cases, but the confession is made invalid by the defect in essential matter which the lie produces; for the confessor does not understand the true state of the penitent’s soul.
(b) There is mortal sin when the lie deceives the confessor about matter that is impertinent to the confession, but is grave in itself, as when the penitent seriously calumniates a neighbor to the priest. In this case the confession is made invalid by the want of disposition on the part of the penitent.
(c) There is light sin when the lie deceives the confessor about free matter which is not the only sin confessed, or which the confessor does not need to know in order substantially to pass judgment and give direction; also when the lie is not serious and is impertinent to the confession. In these cases the Sacrament is not made invalid, for the insincerity does not change the confessor’s decision.