Et chátááj

את חטאי, even though it is not good manners for a person to mention the sins he had committed against his sovereign in his presence after the time had passed for forgiveness, in this instance the cup bearer excuses his mentioning these sins as he does so in the king’s interest.

The chief cupbearer then spoke up and said to Pharaoh, “I must make mention today of my offenses.

Employing parallel language, Rav Kahana also said: I consider impudent one who specifies his transgression, as it is stated: “Happy is he whose iniquity is forgiven, whose transgression is covered over” (Psalms 32:1); one who conceals his transgressions indicates that he is ashamed of them, and due to his shame he will be forgiven.

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את חטאי, “my sins, etc.” he used the plural form in describing his sin, as he had also been guilty of forgetting the promise he had made to Joseph, something he should have kept at once.

If a person transgresses any of the mitzvot of the Torah, whether a positive command or a negative command - whether willingly or inadvertently - when he repents, and returns from his sin, he must confess before God, blessed be He, as [Numbers 5:6-7] states: "If a man or a woman commit any of the sins of man... they must confess the sin that they committed."
This refers to a verbal confession. This confession is a positive command.
How does one confess: He states: "I implore You, God, I sinned, I transgressed, I committed iniquity before You by doing the following. Behold, I regret and am embarrassed for my deeds. I promise never to repeat this act again."
These are the essential elements of the confessional prayer. Whoever confesses profusely and elaborates on these matters is worthy of praise.
Those who bring sin offerings or guilt offerings must also [confess their sins] when they bring their sacrifices for their inadvertent or willful transgressions. Their sacrifices will not atone for their sins until they repent and make a verbal confession as [Leviticus 5:5] states: "He shall confess the sin he has committed upon it."
Similarly, those obligated to be executed or lashed by the court do not attain atonement through their death or lashing unless they repent and confess. Similarly, someone who injures a colleague or damages his property, does not attain atonement, even though he pays him what he owes until he confesses and makes a commitment never to do such a thing again as implied by the phrase [Numbers, loc. cit..], "any of the sins of man."

[WHOSE] TRANSGRESSION IS COVERED OVER. The Psalmist praises one who covers his sins, i.e. he does not tell others that he has sinned. Why is this especially praiseworthy? And the reason that this is praiseworthy is because that when a person does not tell others that he has sinned it shows that he is ashamed that he sinned. However, if one tells others that he has sinned it appears that he is not ashamed about his sin, and we have said earlier in the first perek (12b) whosoever does something, a sin, and is embarrassed because of the sin, he is forgiven immediately. Being embarrassed about the sin which brings about forgiveness is therefore praiseworthy.

It is very praiseworthy for a person who repents to confess in public and to make his sins known to others, revealing the transgressions he committed against his colleagues.
He should tell them: "Though I sinned against so and so, committing the following misdeeds.... Behold, I repent and express my regret." Anyone who, out of pride, conceals his sins and does not reveal them will not achieve complete repentance as [Proverbs 28:13] states: "He who conceals his sins will not succeed."
When does the above apply? In regard to sins between man and man. However, in regard to sins between man and God, it is not necessary to publicize one's [transgressions]. Indeed, revealing them is arrogant. Rather, a person should repent before God, blessed be He, and specifically mention his sins before Him. In public, he should make a general confession. It is to his benefit not to reveal his sins as [Psalms 32:1] states: "Happy is he whose transgression is forgiven, whose sin is covered."

But that is saying solely concerning sins between man and man etc. Likewise concerning known and open sins, though not against man; for even as the sin was public so it is necessary to make the repentance public, and let the sinner feel the disgrace of his misdoings.

for I recognize my transgressions,
and am ever conscious of my sin.

Rav Yehuda said that Rav raised a contradiction: It is written: “Fortunate is he whose transgression is forgiven, whose sin is hidden” (Psalms 32:1), implying that it is inappropriate for one to reveal his sins, and it is written: “He who hides his transgressions shall not prosper” (Proverbs 28:13). He resolved the contradiction as follows: This is not difficult. Here it is referring to a publicized sin; since his sin is public knowledge it is fitting for him to also publicize his repentance. There, it is referring to a sin that is not publicized, in which case it is inappropriate to publicize one’s repentance. Rav Zutra bar Toviya said that Rav Naḥman said: Here, it is referring to sins a person commits against another; he must publicize his repentance so that those who hear him may persuade the other to forgive him. There, it is referring to sins a person commits against God, in which case he need not repent publicly.

The Gemara discusses the propriety of admitting one’s sins in public. Granted, with regard to Judah, it was proper that he admitted his sin in public, as he did so in order that Tamar not be burned innocently. But why did Reuben admit his sin in public? But didn’t Rav Sheshet say: I consider one who specifies his sins in public to be brazen, as one who does so indicates that he is not embarrassed by his actions? The Gemara answers: The reason he admitted his sin in public was in order that his brothers should not be suspected of having committed the deed.