Midrash su Pirkei Avoth 4:11
רַבִּי אֱלִיעֶזֶר בֶּן יַעֲקֹב אוֹמֵר, הָעוֹשֶׂה מִצְוָה אַחַת, קוֹנֶה לוֹ פְרַקְלִיט אֶחָד. וְהָעוֹבֵר עֲבֵרָה אַחַת, קוֹנֶה לוֹ קַטֵּגוֹר אֶחָד. תְּשׁוּבָה וּמַעֲשִׂים טוֹבִים, כִּתְרִיס בִּפְנֵי הַפֻּרְעָנוּת. רַבִּי יוֹחָנָן הַסַּנְדְּלָר אוֹמֵר, כָּל כְּנֵסִיָּה שֶׁהִיא לְשֵׁם שָׁמַיִם, סוֹפָהּ לְהִתְקַיֵּם. וְשֶׁאֵינָהּ לְשֵׁם שָׁמַיִם, אֵין סוֹפָהּ לְהִתְקַיֵּם:
R. Eliezer ben Yaakov dice: Se uno fa una mitzvah, acquisisce per sé un avvocato difensore [cioè un angelo che parla per suo conto.] E se uno commette un peccato, acquisisce per sé un kategor (un procuratore), [vale a dire, un angelo incriminante, (essendo kategor acronimo di "kore tigar", "invocazione di conflitti." Sanegor, l'opposto di kategor è acronimo di "sone tigar", "odiare i conflitti")] R. Yochanan Hasandlar dice: Ogni incontro che è per il bene del cielo è destinato a durare e (ogni incontro che è) non per il bene del cielo non è destinato a durare.
Pirkei DeRabbi Eliezer
REPENTANCE and good deeds are a shield against punishment. Rabbi Ishmael said: If repentance had not been created, the world would not stand. But since repentance has been created, the right hand of the Holy One, blessed be He, is stretched forth to receive the penitent every day, and He says, Repent, ye children of men. "Repent, ye children of men" (Ps. 90:8). Know thou the power of repentance. Come and see from Ahab, king of Israel, for he had robbed, coveted, and murdered, as it is said, "Hast thou killed, and also taken possession?" (1 Kings 21:19). He sent and called for Jehoshaphat, king of Judah, who gave him thrice daily forty stripes, and in fasting and with prayer he rose up early and retired late, before the Holy One, blessed be He, and he did not return any more to his evil deeds. His repentance was accepted, as it is said, || "Seest thou how Ahab humbleth himself before me? Because he humbleth himself before me, I will not bring the evil in his days" (1 Kings 21:29).