From Pope St. John Paul II’s Apostolic Exhortation Familiaris Consortio (1981):
An essential and permanent part of the Christian family’s sanctifying role consists in accepting the call to conversion that the Gospel addresses to all Christians, who do not always remain faithful to the “newness” of the Baptism that constitutes them “saints.” The Christian family too is sometimes unfaithful to the law of baptismal grace and holiness proclaimed anew in the sacrament of marriage.
Repentance and mutual pardon within the bosom of the Christian family, so much a part of daily life, receive their specific sacramental expression in Christian Penance. In the Encyclical Humanæ vitæ, Paul VI wrote of married couples: “And if sin should still keep its hold over them, let them not be discouraged, but rather have recourse with humble perseverance to the mercy of God, which is abundantly poured forth in the sacrament of Penance.”146
The celebration of this sacrament acquires special significance for family life. While they discover in faith that sin contradicts not only the covenant with God, but also the covenant between husband and wife and the communion of the family, the married couple and the other members of the family are led to an encounter with God, who is “rich in mercy,”147 who bestows on them His love which is more powerful than sin,148 and who reconstructs and brings to perfection the marriage covenant and the family communion.
146 Section 25: Acta Apostolicæ Sedis [AAS] 60 (1968), 499.
147 Eph 2:4.
148 Cf. John Paul II, Encyclical Dives in misericordia, 13: AAS 72 (1980), 1218 s.
— Familiaris Consortio 58