The Alter Rebbe explained in the previous chapter that although a penitent should always remember his past sins, his recollection should not lead to a state of ongoing depression or shame; such an attitude would cripple the cardinal principle of serving G‑d with joy. Rather, he should recall his past misdeeds “from afar”—only insofar as they will teach him to be humble before all men.

Moreover, these memories will actually enhance the joy of his Divine service, for they will cause him to accept with happy equanimity all manner of pain and suffering, be it verbal or physical, whether visited upon him from Above or through mortal agents.

In this, the concluding chapter of Iggeret Hateshuvah, the Alter Rebbe explains why these afflictions cause the penitent joy.

The reason for joy1 in the suffering of the body

וְטַעַם הַשִּׂמְחָה בְּיִסּוּרֵי הַגּוּף,

is that it is a great and potent2 favor for the sinning soul,

לְפִי שֶׁהִיא טוֹבָה גְדוֹלָה וַעֲצוּמָה לַנֶּפֶשׁ הַחוֹטֵאת,

to cleanse it in This World,3

לְמָרְקָהּ בָּעוֹלָם הַזֶּה

and to spare it from being scoured in Gehinom.4

וּלְהַצִּילָהּ מֵהַמֵּירוּק בְּגֵּיהִנֹּם

(5This is particularly true in these generations of ours,

(בִּפְרָט בְּדוֹרוֹתֵינוּ אֵלֶּה,

when one cannot endure all the fasts prescribed in the penances of the Arizal, as mentioned earlier on in ch. 3,

שֶׁאֵין בִּיכוֹלֶת לְהִתְעַנּוֹת כְּפִי מִסְפַּר כָּל הַצּוֹמוֹת שֶׁבְּתִיקּוּנֵי תְּשׁוּבָה מֵהָאֲרִ"י זִכְרוֹנוֹ לִבְרָכָה,

fasts imperative for the cleansing of the soul to rescue it from the cleansing of Gehinom.)

הַצְּרִיכוֹת לְמֵירוּק הַנֶּפֶשׁ לְהַצִּילָהּ מִמֵּירוּק בְּגֵּיהִנֹּם).

As Nachmanides writes in the Introduction to his Commentary on Job, that even the sufferings of Job for seventy years bear absolutely no comparison to the suffering of a soul for even one hour in Gehinom,

וּכְמוֹ שֶׁכָּתַב הָרַמְבַּ"ן זִכְרוֹנוֹ לִבְרָכָה בַּהַקְדָּמָה לְפֵירוּשׁ אִיּוֹב, שֶׁאֲפִילוּ יִסּוּרִים שֶׁל אִיּוֹב ע' שָׁנָה – אֵין לָהֶן עֵרֶךְ כְּלָל לְיִסּוּרֵי הַנֶּפֶשׁ שָׁעָה אַחַת בְּגֵּיהִנֹּם,

for “[physical] fire is but one sixtieth [of the fire of Gehinom].”6

כִּי אֵשׁ אֶחָד מִשִּׁשִּׁים וְכוּ'.

It is only that this “world is built by kindness,”7

אֶלָּא לְפִי שֶׁעוֹלָם הַזֶּה "חֶסֶד יִבָּנֶה",

for which reason, through mild suffering in This World, one is saved from severe judgments in the Coming World.

וּבְיִסּוּרִין קַלִּין בָּעוֹלָם הַזֶּה נִיצּוֹל מִדִּינִים קָשִׁים שֶׁל עוֹלָם־הַבָּא,

This is analogous to the movement of a shadow on earth of a handsbreadth,

כִּמְשַׁל הִילּוּךְ וְהַעְתָּקַת הַצֵּל בָּאָרֶץ טֶפַח

which equals the sun’s movement in the sky of thousands of miles….

לְפִי הִילּוּךְ גַּלְגַּל הַשֶּׁמֶשׁ בָּרָקִיעַ אֲלָפִים מִילִין וְכוּ'.

I.e., the sun’s movement of thousands of miles causes a corresponding movement of but a few inches of shadow.

Infinitely more so is this true in the parallel,

וְיֶתֶר עַל כֵּן לְאֵין קֵץ הוּא בַּנִּמְשָׁל,

in the descent of the worlds from level to level, from the most exalted heights until this physical world.

בִּבְחִינַת הִשְׁתַּלְשְׁלוּת הָעוֹלָמוֹת מֵרוּם הַמַּעֲלוֹת עַד עוֹלָם הַזֶּה הַגַּשְׁמִי.

The analogy may be understood as follows: Any event that transpires in this world results from a parallel but far more ethereal event that “previously” took place in the spiritually exalted worlds. Thus, the effect of an event in this physical world is much greater in those lofty worlds.

We see this in the teachings of the Zohar on the elevation of the higher worlds

וְכַנּוֹדָע מִמַּה שֶּׁכָּתוּב בַּזּוֹהַר הַקָּדוֹשׁ, מֵעִנְיַן עֲלִיּוֹת עוֹלָמוֹת הָעֶלְיוֹנִים

as a result of the spiritual arousal initiated by man below through his offering of one fowl, a dove or pigeon, or a handful of meal on the altar.

בְּאִתְעָרוּתָא דִלְתַתָּא, בְּהַקְרָבַת עוֹף אֶחָד בֶּן יוֹנָה אוֹ תוֹר עַל גַּבֵּי הַמִּזְבֵּחַ אוֹ קוֹמֶץ מִנְחָה.

The Zohar teaches that offering but one such representative creature from the animal world or but one such representative item from the vegetative world elevates all the spiritual realms.

Such are the effects of all the commandments requiring practical performance, as is known from the Arizal.

וְכֵן הוּא בְּכָל הַמִּצְוֹת מַעֲשִׂיּוֹת, כַּנּוֹדָע מֵהָאֲרִיזַ"ל.

Mitzvot performed in this world with physical objects, such as tzitzit made of wool or the passages of the tefillin written on parchment, set up far reaching reverberations in the exalted spiritual worlds.

This, too, is our Sages’ comment8 on the verse, “Sanctify yourselves, and you shall be holy”9

וְזֶהוּ שֶׁאָמְרוּ רַבּוֹתֵינוּ־זִכְרוֹנָם־לִבְרָכָה עַל פָּסוּק: "וְהִתְקַדִּשְׁתֶּם וִהְיִיתֶם קְדוֹשִׁים" –

“Man sanctifies himself [only] a little (‘i.e.,’ comments the Rebbe, ‘in quantity’) below (‘i.e.,’ comments the Rebbe, ‘in quality’), and he becomes sanctified in great measure from Above….”

"אָדָם מְקַדֵּשׁ עַצְמוֹ מְעַט מִלְּמַטָּה, מְקַדְּשִׁין אוֹתוֹ הַרְבֵּה מִלְמַעְלָה וְכוּ'"

(10It was thus noted above11 in reference to the phrase, “Who sanctified us with His commandments…,” [that Israel’s sanctification through mitzvot is bound up with the Infinite life-force that] encompasses and transcends all worlds….)

(וּכְמוֹ שֶׁנִּתְבָּאֵר לְעֵיל בְּעִנְיַן "אֲשֶׁר קִדְּשָׁנוּ בְּמִצְוֹתָיו" וְכוּ', בְּחִינַת "סוֹבֵב כָּל עָלְמִין", וְכוּ').

Thus, the physical performance of a Divine commandment in this world draws down upon the individual holiness not only from the most lofty spiritual worlds but also from the degree of G‑dliness that transcends worlds.

Precisely so is it in reference to reward and punishment,

וְכָכָה מַמָּשׁ הוּא בְּעִנְיַן שָׂכָר וְעוֹנֶשׁ,

The reward for the performance of a mitzvah infinitely surpasses the physical deed itself; the punishment as well, suffered by an individual in this world for his sins, substitutes for a far greater measure of punishment that the person would have undergone had it been meted out in the Coming World.

as our Sages say, “The reward of a mitzvah is the mitzvah…,”12

כְּמַאֲמַר רַבּוֹתֵינוּ־זִכְרוֹנָם־לִבְרָכָה: "שְׂכַר מִצְוָה – מִצְוָה וְכוּ'",

I.e., the reward is the spiritual illumination that is drawn down through the fulfillment of the mitzvah itself,

as discussed elsewhere.

וּכְמוֹ שֶׁנִּתְבָּאֵר בְּמָקוֹם אַחֵר.

Since it has just been explained that the performance of a mitzvah draws down as a reward Divine illumination that utterly transcends all worlds, it follows that the reward for the mitzvah in the loftier spiritual worlds is infinitely higher than the physical action performed here below.

This knowledge is elementary to the discerning,

וְדַעַת לְנָבוֹן נָקָל,

and those with intelligence in this matter will discover good.

וּמַשְׂכִּיל עַל דָּבָר יִמְצָא טוֹב: