In line with Luther's initial statement in his Large Catechism, some Lutherans speak of only two sacraments, Baptism and the Eucharist, although later in the same work he calls Confession and Absolution "the third sacrament." The definition of sacrament in the Apology of the Augsburg Confession lists Absolution as one of them. Luther went to confession all his life. Although Lutherans do not consider the other four rites as sacraments, they are still retained and used in the Lutheran church. However, in the nineteenth and twentieth centuries, private confession fell into disuse in many Protestant churches; at the present time, it is among Lutherans, for example, expected before partaking of the Eucharist for the first time. Philipp Melanchthon speaking about the Confession in the Lutheran Church, claims that "we do not wish to sanction the torture [the tyranny of consciences] of the Summists, which notwithstanding would have been less intolerable if they had added one word concerning faith, which comforts and encourages consciences. Now, concerning this faith, which obtains the remission of sins, there is not a syllable in so great a mass of regulations, glosses, summaries, books of confession. Christ is nowhere read there". This polemical view ignores the Catholic emphasis on faith and Christ in Catholic instruction and practice, including regarding confession.
The Catholic Church teaches that "Confession" is one name for the Sacrament, whereas another name, the "Sacrament of Reconciliation", highlights that it is an external expression of internal transformation. It is also the case that Confession is no longer regarded by some as the essence of the sacrament; they prefer to emphasise the aspects of healing and forgiveness. This aspect is of course included in the Catholic Catechism.
The basic form of confession has changed over the centuries. In the early history of the Catholic Church, confessions were made publicly, not only before the priest but also before the congregation. The Penitential Rite at the beginning of the Mass is a liturgical rudiment of this previously sacramental confession. This was discontinued, since for fear of shame it was thought that some might avoid public confession, and private confession became the normal way in which this sacrament was and is practiced, with a strict seal of secrecy on the part of the priest. Sometimes the practice of the sacrament emphasized doing acts of penance, sometimes it emphasized making one's sorrow or contrition authentic, sometimes it emphasized confessing all one's serious (mortal) sins, sometimes it emphasized the power of the priest to absolve the penitent of sin, and currently there are forms that include simply one-on-one confession to a priest or communal preparation and then one-on-one confession to a priest.
Guilt is an important factor in perpetuating Obsessive–compulsive disorder symptoms. Research is mixed on the possible connection between Catholicism and obsessive-compulsive symptoms. A study of 165 individuals by the University of Parma found that religious individuals scored higher on measures of control of thoughts and overimportance of thoughts, and that these measures were associated with obsessive-compulsive symptoms only in the religious participants. Another study noted a link between intrinsic religiosity and obsessive-compulsive cognitions/behaviors only among Catholic participants. However, a study from Boston University found that no particular religion was more common among OCD patients, and that OCD patients were no more religious than other subjects with anxiety. Religious obsessions were connected to the participants' religiosity, but sexual and aggressive symptoms were not. Greater religious devotion among OCD patients was correlated with increased guilt.
A study in American Behavioral Scientist analyzed interviews with participants from Catholic, Jewish, and Protestant backgrounds. The author reported that most participants "eagerly described an experience of guilt." 
University of Ulster students participated in a study that found a slightly higher level of collective guilt among the Catholic students than the Protestant students.
Researchers from the University of California at Berkeley and from the University of Notre Dame examined the concept of Catholic guilt among U.S. teenagers. The authors found no evidence of Catholic guilt in this population, noting that Catholicism both caused and relieved less guilt than other religious traditions. The authors found no evidence that Catholic teenagers experience more guilt than non-Catholic teenagers. The authors did not find that more observant Catholics feel guiltier than less observant Catholics. The study also noted no difference in the effect of guilt-inducing behaviors on Catholic versus non-Catholic participants.
A study from Hofstra University reported no difference in total guilt among religions, although religiosity itself was connected to guilt.
Guilt can be viewed in terms of constructiveness versus destructiveness: "constructive guilt" is focused on forgiving one's ethical lapses and changing one's behavior, while "destructive guilt" remains mired in self-loathing and does not emphasize learning from one's wrongdoings and moving ahead with life. A study in Psychology of Religion found that Catholic participants demonstrated a higher level of constructive guilt reactions than other groups.
Living in sin, with sin, by sin, for sin, every hour, every day, year in, year out. Waking up with sin in the morning, seeing the curtains drawn on sin, bathing it, dressing it, clipping diamonds to it, feeding it, showing it round, giving it a good time, putting it to sleep at night with a tablet of Dial if it's fretful. Always the same, like an idiot child carefully nursed, guarded from the world. 'Poor Julia,' they say, 'she can't go out. She's got to take care of her little sin. A pity it ever lived,' they say, 'but it's so strong. Children like that always are. Julia's so good to her little, mad sin.’ 
Jack Donaghy: That's not how it works, Tracy. Even though there is the whole confession thing, that's no free pass, because there is a crushing guilt that comes with being a Catholic. Whether things are good or bad or you're simply... eating tacos in the park, there is always the crushing guilt [Miming the act of self-flagellation].
Tracy Jordan: I don't think I want that. I'm out.[Jack crosses himself] 
[Jack turns to leave]
Jack Donaghy: [to himself] Somehow, I feel oddly guilty about that.
- Stravinskas, Peter (1990). Catholic Answer Book. Our Sunday Visitor. p. 78. ISBN 0879734582.
- Luther's Large Catechism IV, 1: "We have now finished the three chief parts of the common Christian doctrine. Besides these we have yet to speak of our two Sacraments instituted by Christ, of which also every Christian ought to have at least an ordinary, brief instruction, because without them there can be no Christian; although, alas! hitherto no instruction concerning them has been given" (emphasis added; cf. Theodore G. Tappert, trans. and ed., The Book of Concord: The Confessions of the Evangelical Lutheran Church, (Philadelphia: Fortress Press, 1959), 733).
- John 20:23, and Engelder, T.E.W.Popular Symbolics. St. Louis: Concordia Publishing House, 1934. pp. 112-3, Part XXVI "The Ministry", paragraph 156.
- Luther's Large Catechism IV, 74-75: "And here you see that Baptism, both in its power and signification, comprehends also the third Sacrament, which has been called repentance, as it is really nothing else than Baptism" (emphasis added; cf. Theodore G. Tappert, trans. and ed., The Book of Concord: The Confessions of the Evangelical Lutheran Church, (Philadelphia: Fortress Press, 1959), 751).
- The Apology of the Augsburg Confession XIII, 3, 4: "If we define the sacraments as rites, which have the command of God and to which the promise of grace has been added, it is easy to determine what the sacraments are, properly speaking. For humanly instituted rites are not sacraments, properly speaking, because human beings do not have the authority to promise grace. Therefore signs instituted without the command of God are not sure signs of grace, even though they perhaps serve to teach or admonish the common folk. Therefore, the sacraments are actually baptism, the Lord’s Supper, and absolution (the sacrament of repentance)" (cf. Tappert, 211).
- "Article XIII. (VII): Of the Number and Use of the Sacraments.". bookofconcord.org. 2011 [last update]. Retrieved 8 October 2011.
- Apology of the Augsburg Confession, article 24, paragraph 1. Retrieved 2010-02-02.
- "Defense of the Augsburg Confession". Book of Concord. Retrieved 2013-11-02.
- "Update Your Faith". American Catholic. Retrieved 2013-11-02.
- Catechism of the Catholic Church (no.1449): "The sacrament of penance & reconciliation: The formula of absolution used in the Latin Church expresses the essential elements of this sacrament: the Father of mercies is the source of all forgiveness. He effects the reconciliation of sinners through the Passover of his Son and the gift of his Spirit, through the prayer and ministry of the Church: God, the Father of mercies, through the death and the resurrection of his Son has reconciled the world to himself, and sent the Holy Spirit among us for the forgiveness of sins; through the ministry of the Church may God give you pardon and peace, and I absolve you from your sins in the name of the Father, and of the Son and of the Holy Spirit." See also op.cit., no.1422
- Hanna, E. (1911). The Sacrament of Penance. In The Catholic Encyclopedia. New York: Robert Appleton Company. Retrieved September 14, 2008 from New Advent: http://www.newadvent.org/cathen/11618c.htm
- Gula, Richard M. (1984-05-01). To Walk Together Again: The Sacrament of Reconciliation. Paulist Press. ISBN 978-0-8091-2603-3.
- Leslie J. Shapiro, LICSW. "Pathological guilt: A persistent yet overlooked treatment factor in obsessive-compulsive disorder —". Aacp.com. Retrieved 2013-11-02.
- "Religiousness and obsessive–compulsive cognitions and symptoms in an Italian population". Sciencedirect.com. 2002-07-31. Retrieved 2013-11-02.
- "Personality predictors of religious orientation among Protestant, Catholic, and non-religious college students". Sciencedirect.com. 1998-02-28. Retrieved 2013-11-02.
- "Religion and guilt in OCD patients". Sciencedirect.com. 1991-12-31. Retrieved 2013-11-02.
- "Collective Guilt: International Perspectives - Google Books". Books.google.com. Retrieved 2013-11-02.
- "Predicting guilt from irrational beliefs, religious affiliation and religiosity - Springer". Springerlink.com. 1988-12-01. Retrieved 2013-11-02.
- "ingentaconnect Guilt and Religion: The influence of orthodox Protestant and orth". Ingentaconnect.com. 2005-01-01. Retrieved 2013-11-02.
- "on Julia Flyte". Shmoop.com. Retrieved 2013-11-02.
- IMDB 30 Rock
- Sheldon, Kennon M.; University of Missouri-Columbia (2006). "RESEARCH: Catholic Guilt? Comparing Catholics' and Protestants' Religious Motivations". International Journal for the Psychology of Religion (Lawrence Erlbaum Associates, Inc.) 16 (3): 209–223. doi:10.1207/s15327582ijpr1603_5.
- Mallon, John (2006-04). "The Primacy of Jesus, the Primacy of Love". Inside the Vatican. Retrieved 2006-11-01.
- Hill, James (2012-04). "My First Visit to a Non-Catholic Church". Christians for Christ Web Site. Christians for Christ Ministries. Retrieved 2012-05.