אמר ר' יוחנן
Steinsaltz, Adin. "Repentance." The Thirteen Petalled Rose. New York: Basic, 1980. 133. Print.
The act of repentance is, in the first place, a severance of the chain of cause and effect in which one transgression follows inevitably upon another. Beyond this, it is an attempt to nullify and even alter the past. This can be achieved only when man, subjectively, shatters the order of his own existence. The trust of repentance is to break through the ordinary limits of the self.
Heschel, Abraham Joshua, and Susannah Heschel. "The Meaning of Repentance." Moral Grandeur and Spiritual Audacity: Essays. New York: Farrar, Straus & Giroux, 1997. 69. Print.
The most unnoticed of all miracles is the miracle of repentance. It is not the same thing as rebirth; it is transformation, creation. In the dimension of time there is no going back. But the power of repentance causes time to be created backward and allows re-creation of the past to take place. Through the forgiving hand of God, harm and blemish which we have committed against the world and against ourselves will be extinguished, transformed into salvation.
God brings about this creation for the sake of humanity when a human being repents for the sake of God.
For many years we have experienced history as a judgment. What is the state of our repentance, of our "return to Judaism"?
Repentance is an absolute, spiritual decision made in truthfulness. Its motivations are remorse for the past and responsibility for the future. Only in this manner is it possible and valid.
(א) כָּל מִצְוֹת שֶׁבַּתּוֹרָה בֵּין עֲשֵׂה בֵּין לֹא תַּעֲשֶׂה אִם עָבַר אָדָם עַל אַחַת מֵהֶן בֵּין בְּזָדוֹן בֵּין בִּשְׁגָגָה כְּשֶׁיַּעֲשֶׂה תְּשׁוּבָה וְיָשׁוּב מֵחֶטְאוֹ חַיָּב לְהִתְוַדּוֹת לִפְנֵי הָאֵל בָּרוּךְ הוּא שֶׁנֶּאֱמַר (במדבר ה-ו) "אִישׁ אוֹ אִשָּׁה כִּי יַעֲשׂוּ" וְגוֹ' (במדבר ה-ז) "וְהִתְוַדּוּ אֶת חַטָּאתָם אֲשֶׁר עָשׂוּ" זֶה וִדּוּי דְּבָרִים. וִדּוּי זֶה מִצְוַת עֲשֵׂה. כֵּיצַד מִתְוַדִּין. אוֹמֵר אָנָּא הַשֵּׁם חָטָאתִי עָוִיתִי פָּשַׁעְתִּי לְפָנֶיךָ וְעָשִׂיתִי כָּךְ וְכָךְ וַהֲרֵי נִחַמְתִּי וּבֹשְׁתִּי בְּמַעֲשַׂי וּלְעוֹלָם אֵינִי חוֹזֵר לְדָבָר זֶה. וְזֶהוּ עִקָּרוֹ שֶׁל וִדּוּי. וְכָל הַמַּרְבֶּה לְהִתְוַדּוֹת וּמַאֲרִיךְ בְּעִנְיָן זֶה הֲרֵי זֶה מְשֻׁבָּח. וְכֵן בַּעֲלֵי חַטָּאוֹת וַאֲשָׁמוֹת בְּעֵת שֶׁמְּבִיאִין קָרְבְּנוֹתֵיהֶן עַל שִׁגְגָתָן אוֹ עַל זְדוֹנָן אֵין מִתְכַּפֵּר לָהֶן בְּקָרְבָּנָם עַד שֶׁיַּעֲשׂוּ תְּשׁוּבָה וְיִתְוַדּוּ וִדּוּי דְּבָרִים שֶׁנֶּאֱמַר (ויקרא ה-ה) "וְהִתְוַדָּה אֲשֶׁר חָטָא עָלֶיהָ". וְכֵן כָּל מְחֻיְּבֵי מִיתוֹת בֵּית דִּין וּמְחֻיְּבֵי מַלְקוֹת אֵין מִתְכַּפֵּר לָהֶן בְּמִיתָתָן אוֹ בִּלְקִיָּתָן עַד שֶׁיַּעֲשׂוּ תְּשׁוּבָה וְיִתְוַדּוּ. וְכֵן הַחוֹבֵל בַּחֲבֵרוֹ וְהַמַּזִּיק מָמוֹנוֹ אַף עַל פִּי שֶׁשִּׁלֵּם לוֹ מַה שֶּׁהוּא חַיָּב לוֹ אֵינוֹ מִתְכַּפֵּר עַד שֶׁיִּתְוַדֶּה וְיָשׁוּב מִלַּעֲשׂוֹת כָּזֶה לְעוֹלָם שֶׁנֶּאֱמַר (במדבר ה-ו) "מִכָּל חַטֹּאת הָאָדָם":
(1) All of the commandments in the Torah: whether they be the positive commandments, or the negative commandments; if a person transgressed any of them, whether he did so intentionally, whether he did so unintentionally, when he repents and returns from his sin - he is obligated to confess before God, blessed be He, as it says (Numbers 5:6-7), When a man or a women does any of the sins of man...and he shall confess his sin that he committed... - this refers to a verbal confession. And confession, that is a positive commandment. How does he confess? He says, "Please God, I have sinned, I have erred, I have [willfully but unrebelliously] transgressed, I have done such-and-such [specific sins], I am regretful, and ashamed for my actions, and I will never again return to my old ways." This is the essence of the confession, and anyone who wants to lengthen [his confession], this is praiseworthy.And it is the same for those who are liable for sin [hattat] and guilt [asham] sacrifices: at the time when they bring sacrifices for their unintentional or intentional sins, [the sacrifices] do not atone for them until they repent [do teshuvah] and confess verbally [do vidui], as it says, he shall confess the matter in which he sinned (Leviticus 5:5). So too for those who are liable for capital punishment or lashes: their death or lashing does not atone for them until they repent [do teshuvah] and confess verbally [do vidui]. And also someone who has injured his fellow or damaged his property, even though he has repaid what he owes him, he has not atoned until he confesses and turns away from similar actions forever, as it says, From any of the sins of man (Numbers 5:6).
Steinsaltz, Adin. "Repentance." The Thirteen Petalled Rose. New York: Basic, 1980. 125 Print
Certain sages go so far as to include Repentance among the entities created before the world itself.