343. HE ASKS, "And into which place did earth admit him?" AND HE SAYS, into Arka, WHICH IS ONE OF THE SEVEN PHYSICAL LEVELS OF EARTH. Of all who reside there, it is written: "these shall perish from the earth and from beneath the heavens" (Yirmeyah 10:11). There, he established his place of living. This place is referred to in the words: "And he dwelt in the land of Nod east of Eden" (Beresheet 4:16). THIS ALLUDES TO THE LOWER COMPARTMENT CALLED 'ARKA.' THIS COMPARTMENT IS ALSO CALLED "NOD (SWAY)," BECAUSE THE RESIDENTS HAVE TWO HEADS AND SWAY FROM ONE SIDE OF DARKNESS TO THE OTHER SIDE OF LIGHT.
343. וּבְאָן אֲתַר קַבֵּילַת לֵיהּ אַרְעָא, בְּאַרְקָא. וְכָל אִינוּן דְּדָיְירֵי תַּמָּן. עֲלֵיהוֹן כְּתִיב יֹאבְדוּ מֵאַרְעָא וּמִתְּחוֹת שְׁמַיָא אֵלֶּה. וְתַמָּן שַׁוֵּי מְדוֹרֵיהּ, וְהַיְינוּ דִּכְתִיב, וַיֵּשֶׁב בְּאֶרֶץ נוֹד קִדְמַת עֵדֶן.
344. Tosefta (Addendum). When Cain said, "My punishment is greater than I can bear" (Beresheet 4:13), MEANING AFTER HE CONFESSED AND REPENTED, the Holy One, blessed be He, withdrew one half of his punishment. In the original punishment, He stated: "you shall be a fugitive (Heb. na) and a vagabond (Heb. nad) on the earth" (Ibid. 12), but now he stayed only in Nod. And so it is written: "And Cain when out from the presence of Hashem and dwelt in the land of Nod" (Ibid. 16), meaning that he left the presence of Hashem to be a vagabond, but not a fugitive, on the earth, BECAUSE HALF HIS PUNISHMENT HAD BEEN WITHDRAWN.
344. תּוֹסֶפְתָּא כֵּיוָן דַּאֲמַר קַיִן, גָּדוֹל עֲוֹנִי מִנְשֹׂא. מָחַל לֵיהּ קֻדְשָׁא בְּרִיךְ הוּא, פַּלְגוּ מֵעוֹנְשֵׁיהּ. בְּגִין דְּגָזַר עֲלֵיהּ בְּקַדְמֵיתָא, וַאֲמַר לֵיהּ, נָע וָנָד תִּהְיֶה בָאָרֶץ. וְהַשְׁתָּא, אִשְׁתָּאַר בְּנוֹד בִּלְחוֹדוֹי. הה"ד וַיֵּצֵא קַיִן מִלִּפְנֵי ה' וגו'. כְּלוֹמַר, דְּכַד נָפַק מִן קֳדָם ה' הֲוָה, בְּגִין לְמֶהֱוֵי נָד בְּאַרְעָא, וְלָא נָע.
345. THE RABBIS further said that when Cain left the presence of Hashem, Adam asked him, 'My son, what was done with your sentence?' Cain replied, 'Father, I was already given the good news that the Holy One, blessed be He, has forgiven me and that I can reside in Nod alone.' Adam then asked him, 'How did you merit that?' and Cain answered, 'Because I repented and confessed before Him.' Adam said, 'The strength of repentance is so great and powerful, and I did not know that.' He began to say praises to his Master and to thank him. He started reciting "A song for the day of Shabbat. It is good to thank Hashem" (Tehilim 92:1). For it is good to praise, repent, and thank before the Holy One, blessed be He. End of Tosefta (Addendum).
345. וְעוֹד אֲמָרוּ, כַּד נָפַק קַיִן, מִן קֳדָם ה', אֲמַר לוֹ אָדָם, בְּרִי, מָה אִתְעֲבֵיד עַל דִּינָךְ. אֲמַר לוֹ קַיִן, אַבָּא, כְּבָר אִתְבַּשְׂרִית, דִּמְחַל לִי קֻדְשָׁא בְּרִיךְ הוּא, בְּנוֹד בִּלְחוֹדוֹי. אֲמַר לוֹ, הֵיאַךְ הוּא. אֲמַר לוֹ, בְּגִין דְּתָבִית, וְאוֹדִית קַמֵּיהּ. אֲמַר אָדָם, וְכִי דֵּין הוּא רַב וְתַקֵּיף חֵילָא דִתְשׁוּבָה, וַאֲנָא לָא יְדִיעַת. שְׁרָא לְשַׁבְּחָא לְמָרֵיהּ, וּלְאוֹדָאָה לֵיהּ, פְּתַח וַאֲמַר, מִזְמוֹר שִׁיר לְיוֹם הַשַּׁבָּת טוֹב לְהוֹדוֹת לַה'. כְּלוֹמַר, טוֹב לְשַׁבָּחָא וְלַאֲתָבָא וּלְאוֹדָאָה קַמֵּיהּ קֻדְשָׁא בְּרִיךְ הוּא (ע"כ תוספתא)