The fourth step of teshuvah is vidui, verbal confession. Rambam’s presentation of vidui seems to count it as the mitsvah, not the repentance itself. He opens Hilkhot Teshuvah by saying that when a sinner repents his sin, he must recite the vidui. The Rov ztllh"h convincingly claimed that Rambam only counted vidui as the mitsvah because it is the act that expresses the completion of teshuvah. Others, I would note, advanced different suggestions; some even questioned whether Rambam thought there was a requirement to repent. In their opinion, teshuvah was an opportunity—a chance to repair our relationship with God—rather than an obligation.

Whether or not we accept the Rov’s view , I would note that there were authorities who codified a Torah obligation to recite vidui on Yom Kippur. According to these authorities, when the High Priest on Yom Kippur addressed the people and said "Lifnei Hashem Titharu, you shall be purified before God," it was a command, not a statement. At least on Yom Kippur, then, there might be a specific requirement to repent, ending with a recitation of vidui.

While we nowadays have a set form for vidui (actually two—the ashamnu, bagadnu prayer and the `al het prayer), that is not a requirement. As Rambam expresses it in the first chapter of Hilkhot Teshuvah, the vidui can just take the form of "Oh, God, I have sinned before you, and done this, and this, and this, and I am embarrassed by my actions, and will not return to them again." The central part of this vidui, of course, is the detailing of one’s sin.

Detailing sin involves two different endeavors. First, detail means specifying all the different types of sin one has committed—it would clearly not suffice to say "God, I’ve done a lot of wrong things, I’m ashamed and will not do them again." Instead, we would have to list them—I haven’t learned Torah when I could, I haven’t davened with enough attention, I haven’t paid the proper attention to my wife and family, etc. In addition, though, vidui ideally includes details about each specific sin.

It would be preferable (as Rambam says) to speak lengthily about the sin. That would mean that we would not just confess to God that we spoke lashon hara (to use an example that sadly applies to the broad range of people). Rather, we should ideally review the details of the sin—the circumstances that drew us in to saying lashon hara, the insecurities that led us to want to speak ill of others, the kinds of friends we have who encourage that kind of conversation as opposed to other, more positive forms of discussion, etc.

If we do that, vidui becomes more than confession, it’s personal analysis. It is not only that we notice a result, are upset by it, and resolve not to do it again. We notice all the steps that led up to it, the prior factors that led us ever closer to that final act of sin. That process both helps us fully know our sin and also helps us begin to safeguard ourselves from future sin. Forewarned about our personal danger factors of sin means we are forearmed in avoiding it.

In this context, the Rov noted that the Talmud discusses the rehabilitation of a sinner who has been considered an invalid witness in court by virtue of his sins. Such a penitent the Talmud says, he must destroy the vehicle of those sins before he can be accepted as a witness. Detailed vidui helps us not only leave the sin, but identify and avoid the path that led to it.

One more interesting aspect of vidui is the question of whether it is meant to be a private or a public experience. We assume that confession is completely between a person and God. Halakhah, however, likes the notion of public confession, at least for interpersonal sins. In foregoing our public dignity to make full amends to someone we have wronged, we demonstrate our commitment to repairing our crime. Such public abasement also sets an example for others— were our society to be one where people willingly confessed publicly the interpersonal sins they had committed, I fully believe there would be fewer of those sins as well.

There are two exceptions to the preference for public sin. First, if the confession will embarrass the wronged person, we should not do it—think of Winston Churchill being forced to apologize for a comment about another member of Parliament. He said, "It has been said that yesterday I called the distinguished member a ________. It is true, and I am sorry." Second, in sins that relate only to God, halakhah worries that confession will seem too much like pride— look at what I did that annoyed God, kivayakhol, as it were. That reasoning leads Rabad to believe that if the public already knew of the sin—so the confession isn’t putting new information in the public domain, isn’t revealing a breach of the disipline that God conveyed to the Jewish people—public vidui would be worthwhile. This split between interpersonal and ritual sins comes from a contrast in verses, one saying that hiding one’s sins is an ultimately unsuccessful strategy, the other saying that one whose sins are hidden should be pleased. The explanation of the split suggests that our relationship with God directly is, indeed, a private matter, but our working within society is properly the concern of all members of that society.