זְכוּת דְּמִצְוָה מִי מַגְּנָא כּוּלֵּי הַאי? וְהָתַנְיָא: אֶת זוֹ דָּרַשׁ רַבִּי מְנַחֵם בַּר יוֹסֵי: ״כִּי נֵר מִצְוָה וְתוֹרָה אוֹר״, תָּלָה הַכָּתוּב אֶת הַמִּצְוָה בְּנֵר, וְאֶת הַתּוֹרָה בְּאוֹר. אֶת הַמִּצְוָה בְּנֵר, לוֹמַר לָךְ: מָה נֵר אֵינָהּ מְגִינָּה אֶלָּא לְפִי שָׁעָה — אַף מִצְוָה אֵינָהּ מְגִינָּה אֶלָּא לְפִי שָׁעָה. וְאֶת הַתּוֹרָה בְּאוֹר, לוֹמַר לָךְ: מָה אוֹר מֵגֵין לָעוֹלָם, אַף תּוֹרָה מְגִינָּה לָעוֹלָם. וְאוֹמֵר: ״בְּהִתְהַלֶּכְךָ תַּנְחֶה אֹתָךְ וְגוֹ׳״. ״בְּהִתְהַלֶּכְךָ תַּנְחֶה אֹתָךְ״ — זֶה הָעוֹלָם הַזֶּה. ״בְּשָׁכְבְּךָ תִּשְׁמוֹר עָלֶיךָ״ — זוֹ מִיתָה. ״וַהֲקִיצוֹתָ הִיא תְשִׂיחֶךָ״ — לֶעָתִיד לָבֹא. מָשָׁל לְאָדָם שֶׁהָיָה מְהַלֵּךְ בְּאִישׁוֹן לַיְלָה וַאֲפֵילָה, וּמִתְיָירֵא מִן הַקּוֹצִים וּמִן הַפְּחָתִים וּמִן הַבַּרְקָנִים, וּמֵחַיָּה רָעָה וּמִן הַלִּסְטִין, וְאֵינוֹ יוֹדֵעַ בְּאֵיזֶה דֶּרֶךְ מְהַלֵּךְ. נִזְדַּמְּנָה לוֹ אֲבוּקָה שֶׁל אוּר — נִיצַּל מִן הַקּוֹצִים וּמִן הַפְּחָתִים וּמִן הַבַּרְקָנִים, וַעֲדַיִין מִתְיָירֵא מֵחַיָּה רָעָה וּמִן הַלִּיסְטִין, וְאֵינוֹ יוֹדֵעַ בְּאֵיזֶה דֶּרֶךְ מְהַלֵּךְ. כֵּיוָן שֶׁעָלָה עַמּוּד הַשַּׁחַר — נִיצַּל מֵחַיָּה רָעָה וּמִן הַלִּיסְטִין, וַעֲדַיִין אֵינוֹ יוֹדֵעַ בְּאֵיזֶה דֶּרֶךְ מְהַלֵּךְ. הִגִּיעַ לְפָרָשַׁת דְּרָכִים — נִיצַּל מִכּוּלָּם.
The Gemara asks: Does the merit of a mitzva protect one so much as to delay her punishment? But isn’t it taught in a baraita: Rabbi Menaḥem bar Yosei interpreted this verse homiletically: “For the mitzva is a lamp and the Torah is light” (Proverbs 6:23). The verse associates the mitzva with a lamp and the Torah with the light of the sun. The mitzva is associated with a lamp in order to say to you: Just as a lamp does not protect one by its light extensively but only temporarily, while the lamp is in one’s hand, so too, a mitzva protects one only temporarily, i.e., while one is performing the mitzva. And the Torah is associated with light in order to say to you: Just as the light of the sun protects one forever, so too, the Torah one studies protects one forever; and it states in the previous verse with regard to the Torah: “When you walk, it shall lead you; when you lie down, it shall watch over you; and when you awake, it shall talk with you” (Proverbs 6:22). The Gemara explains: “When you walk, it shall lead you”; this is referring to when one is in this world. “When you lie down, it shall watch over you”; this is referring to the time of death, when one lies in his grave. “And when you awake, it shall talk with you”; this is referring to the time to come after the resurrection of the dead. The Torah that one studies protects and guides him both in this world and in the next world. This can be illustrated by a parable, as it is comparable to a man who is walking in the blackness of night and the darkness, and he is afraid of the thorns, and of the pits, and of the thistles, which he cannot see due to the darkness. And he is also afraid of the wild animals and of the bandits that lurk at night, and he does not know which way he is walking. If a torch of fire comes his way, which is analogous to a mitzva, he is safe from the thorns and from the pits and from the thistles, but he is still afraid of the wild animals and of the bandits, and still does not know which way he is walking. Once the light of dawn rises, which is analogous to Torah study, he is safe from the wild animals and from the bandits, which no longer roam the roads, but he still does not know which way he is walking. If he arrives at a crossroads and recognizes the way, he is saved from all of them.