Tehillim Yahel Ohr ad loc.
(טו) יי אֱלֹקִים, לְמֶלֶךְ שֶׁהָיוּ לוֹ כּוֹסוֹת רֵיקִים, אָמַר הַמֶּלֶךְ אִם אֲנִי נוֹתֵן לְתוֹכָן חַמִּין, הֵם מִתְבַּקְּעִין. צוֹנֵן, הֵם מַקְרִיסִין, וּמֶה עָשָׂה הַמֶּלֶךְ עֵרַב חֲמִין בְּצוֹנֵן וְנָתַן בָּהֶם וְעָמָדוּ. כָּךְ אָמַר הַקָּדוֹשׁ בָּרוּךְ הוּא אִם בּוֹרֵא אֲנִי אֶת הָעוֹלָם בְּמִדַּת הָרַחֲמִים, הֲוֵי חֶטְיָיה סַגִּיאִין. בְּמִדַּת הַדִּין, הָאֵיךְ הָעוֹלָם יָכוֹל לַעֲמֹד. אֶלָּא הֲרֵי אֲנִי בּוֹרֵא אוֹתוֹ בְּמִדַּת הַדִּין וּבְמִדַּת הָרַחֲמִים, וְהַלְּוַאי יַעֲמֹד.
[The verse states “on the day that the Lord G-d made earth and heaven.”] The words “the Lord G-d” can be explained with the following analogy: A king had empty cups. He said, “if I pour hot water in the cups, they will crack; if I pour cold water into them, they will contract.” What did the king do? He mixed the cold and hot water and poured it into the cups, and they held.
In similar fashion, G-d said, “If I create the world with the attribute of mercy alone, there will be a plethora of sinners; if I create it only with the attribute of
judgment—how will the world survive? Rather, I will create it with both attributes, and it shall survive.”
cited in Yahel Ohr ibid.
My grandfather the Rebbe gave a parable to explain the matter from a person who owed his creditor a very large sum of money. If the creditor makes an agreement to accept only half and is willing to receive it incrementally over an extended period of
time, then the borrower will make every effort to repay the debt to the best of his ability. But if the creditor is stubborn and insists on the full payment, the borrower will simply give up and will not pay anything at all. The same is true with regards to teshuvah.
רב הונא תקיפו ליה ארבע מאה דני דחמרא על לגביה רב יהודה אחוה דרב סלא חסידא ורבנן ואמרי לה רב אדא בר אהבה ורבנן ואמרו ליה לעיין מר במיליה אמר להו ומי חשידנא בעינייכו אמרו ליה מי חשיד קודשא בריך הוא דעביד דינא בלא דינא אמר להו אי איכא מאן דשמיע עלי מלתא לימא אמרו ליה הכי שמיע לן דלא יהיב מר שבישא לאריסיה אמר להו מי קא שביק לי מידי מיניה הא קא גניב ליה כוליה אמרו ליה היינו דאמרי אינשי בתר גנבא גנוב וטעמא טעים אמר להו קבילנא עלי דיהיבנא ליה
איכא דאמרי הדר חלא והוה חמרא ואיכא דאמרי אייקר חלא ואיזדבן בדמי דחמרא:
The Gemara relates another story regarding acknowledgement of the justice of divine punishment: Four hundred barrels of Rav Huna’s wine fermented and turned into vinegar, causing him great financial loss.
Rav Yehuda, the brother of Rav Sala the Pious, along with the Sages, and some say Rav Adda bar Ahava, along with the Sages, entered to visit him, and said: The Master should examine his actions, as perhaps he committed a transgression for which he is being punished.
Rav Huna said to them: Am I suspect in your eyes? Have I committed a transgression on account of which you advise me to examine my behavior?
They said to him: Is the Holy One, Blessed be He, suspect that He exacts punishment without justice? Your loss was certainly just, and you must examine your conduct to find out why. The Sages were aware of a flaw in Rav Huna’s conduct, to which they alluded (Tosafot).
Rav Huna said to them: If someone has heard something improper that I have done, let him say so. They said to him: We have heard that the Master does not give a share of his grapevines to his tenant farmers. A tenant farmer is entitled to a portion of the crop grown on his landlord’s property, as well as a share of the vines planted during a given year. Rav Huna said to them: Does this tenant farmer leave me anything from the produce that he grows on my property? He steals it all. Consequently, in denying him his share of the grapevines I am simply recouping that which was stolen from me by this tenant farmer.
They said to him: That is the meaning of the folk saying: One who steals from a thief has a taste of theft. Despite the fact that the property was stolen to begin with, one nevertheless engages in theft. Although he did not violate a prohibition per se, it is still a form of theft, and one who is held to a higher standard than others will be punished for it.
He said to them: I accept upon myself to give my tenant farmer his portion in the future.
Thereupon, as a result of Rav Huna’s repentance, God restored his loss.
Some say his vinegar turned back into wine, and some say that the price of vinegar rose and it was sold at the price of wine.
Reish Lakish said: Great is repentance, as the penitent’s intentional sins are counted for him as unwitting transgressions, as it is stated: “Return, Israel, to the Lord your God, for you have stumbled in your iniquity” (Hosea 14:2).
The Gemara analyzes this: Doesn’t “iniquity” mean an intentional sin? Yet the prophet calls it stumbling, implying that one who repents is considered as though he only stumbled accidentally in his transgression.
The Gemara asks: Is that so? Didn’t Reish Lakish himself say: Great is repentance, as one’s intentional sins are counted for him as merits, as it is stated: “And when the wicked turns from his wickedness, and does that which is lawful and right, he shall live thereby” (Ezekiel 33:19), and all his deeds, even his transgressions, will become praiseworthy?
The Gemara reconciles: This is not difficult: Here, when one repents out of love, his sins become like merits; there, when one repents out of fear, his sins are counted as unwitting transgressions.
...עד שיעשה תשובה גדולה כל כך שזדונות נעשה לו כזכויות ממש, שהיא תשובה מאהבה מעומקא דליבא באהבה רבה וחשיקה ונפש שוקקה לדבקה בו יתברך, וצמאה נפשו ליי כארץ עיפה וציה, להיות כי עד הנה היתה נפשו בארץ ציה וצלמות, היא הסטרא אחרא, ורחוקה מאור פני יי בתכלית. ולזאת צמאה נפשו ביתר עוז מצמאון נפשות הצדיקים, כמאמרם ז"ל: "במקום שבעלי תשובה עומדים" כו'. ועל תשובה מאהבה רבה זו אמרו שזדונות נעשו לו כזכויות, הואיל ועל ידי זה בא לאהבה רבה זו.
A person who makes himself a sukkah recites the blessing “...Who commanded us to make a sukkah.” A person who makes himself a lulav for himself recites the blessing “...Who commanded us to make a lulav.”
[39 Volumes by the Lubavitcher Rebbe]
The simple explanation why such actions warrant a blessing is as follows: If the Torah commanded us to perform certain mitzvot, and these mitzvot cannot be fulfilled without certain preparatory steps, it follows that those actions are also part of
the mitzvah itself (or, that they gain an importance equivalent to the mitzvah).
[Leading halachist and kabbalist, successful orator, poet, author of more than 50 works; Succeeded his father as chief rabbi of Baghdad in 1859. Best known as author of his halachic work, Ben Ish Chai, by which title he is also known. Also popular is his commentary on the homiletical section of the Talmud, called Ben Yehoyadah.]
One can suggest the following symbolism: According to the opinion which maintains that the vinegar rose in value, this alludes to the power of teshuvah—that the very blemish turned into the cure.

