The Confiteor, Misereatur and Indulgentiam function as sacramentals. They “include the acts of penance, sorrow, love and humility by which the just obtain remission of venial sins.” They cannot substitute for the absolution in the Sacrament of Penance if one is in a state of mortal sin. As a ceremonial preparation for Mass, they express the need of the ministers to be cleansed from fault so that they may worthily assist in the highest act of public worship for Catholics
The idea of a confession of sin is supported in part, by reference to the text of James 5:16 “Confess your sins to one another and pray for one another that you might be saved” Not only do the ministers confess to those on earth but those in heaven. This is based on the Catholic doctrine of the Communion of Saints and the belief in the intercession of the saints. In addition to confessing to saints as part of the body of Christ, the Scripture verses often adduced to support this are Matthew 19:28 “Amen, Amen Amen, I say to you, that you, who have followed me, in the regeneration, when the Son of man shall sit on the seat of his majesty, you also shall sit on twelve seats judging the twelve tribes of Israel.” (DR) and 1 Corinthians 6:2 “Know you not that the saints shall judge this world?” (DR) Thus the saints in the Confiteor are both judges and intercessors.
The Latin Dictionary of Lewis and Short - F.F. Bruce (1910-1990), *In Retrospect: Remembrance of Things Past* (Grand Rapids: William B. Eerdmans Publishing Company, 1980), pp. 274-275: Alexander S...
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