The Mishnah lists 48 qualities through which Torah is acquired, including staying up at night (sheinah mema'etet — minimizing sleep). The all-night Shavuot vigil embodies this principle: Torah demands wakefulness and is acquired through sacrifice of sleep.
גְּדוֹלָה תוֹרָה יוֹתֵר מִן הַכְּהֻנָּה וּמִן הַמַּלְכוּת, שֶׁהַמַּלְכוּת נִקְנֵית בִּשְׁלֹשִׁים מַעֲלוֹת, וְהַכְּהֻנָּה בְּעֶשְׂרִים וְאַרְבַּע, וְהַתּוֹרָה נִקְנֵית בְּאַרְבָּעִים וּשְׁמֹנָה דְבָרִים. וְאֵלוּ הֵן, בְּתַלְמוּד, בִּשְׁמִיעַת הָאֹזֶן, בַּעֲרִיכַת שְׂפָתַיִם, בְּבִינַת הַלֵּב, בְּשִׂכְלוּת הַלֵּב, בְּאֵימָה, בְּיִרְאָה, בַּעֲנָוָה, בְּשִׂמְחָה, בְּטָהֳרָה, בְּשִׁמּוּשׁ חֲכָמִים, בְּדִקְדּוּק חֲבֵרִים, וּבְפִלְפּוּל הַתַּלְמִידִים, בְּיִשּׁוּב, בַּמִּקְרָא, בַּמִּשְׁנָה, בְּמִעוּט סְחוֹרָה, בְּמִעוּט דֶּרֶךְ אֶרֶץ, בְּמִעוּט תַּעֲנוּג, בְּמִעוּט שֵׁינָה, בְּמִעוּט שִׂיחָה, בְּמִעוּט שְׂחוֹק, בְּאֶרֶךְ אַפַּיִם, בְּלֵב טוֹב, בֶּאֱמוּנַת חֲכָמִים, וּבְקַבָּלַת הַיִּסּוּרִין, הַמַּכִּיר אֶת מְקוֹמוֹ, וְהַשָּׂמֵחַ בְּחֶלְקוֹ, וְהָעוֹשֶׂה סְיָג לִדְבָרָיו, וְאֵינוֹ מַחֲזִיק טוֹבָה לְעַצְמוֹ, אָהוּב, אוֹהֵב אֶת הַמָּקוֹם, אוֹהֵב אֶת הַבְּרִיּוֹת, אוֹהֵב אֶת הַצְּדָקוֹת, אוֹהֵב אֶת הַמֵּישָׁרִים, אוֹהֵב אֶת הַתּוֹכָחוֹת, מִתְרַחֵק מִן הַכָּבוֹד, וְלֹא מֵגִיס לִבּוֹ בְתַלְמוּדוֹ, וְאֵינוֹ שָׂמֵחַ בְּהוֹרָאָה, נוֹשֵׂא בְעֹל עִם חֲבֵרוֹ, מַכְרִיעוֹ לְכַף זְכוּת, מַעֲמִידוֹ עַל הָאֱמֶת, וּמַעֲמִידוֹ עַל הַשָּׁלוֹם, מִתְיַשֵּׁב לִבּוֹ בְתַלְמוּדוֹ, שׁוֹאֵל וּמֵשִׁיב, שׁוֹמֵעַ וּמוֹסִיף, הַלּוֹמֵד עַל מְנָת לְלַמֵּד וְהַלּוֹמֵד עַל מְנָת לַעֲשׂוֹת, הַמַּחְכִּים אֶת רַבּוֹ, וְהַמְכַוֵּן אֶת שְׁמוּעָתוֹ, וְהָאוֹמֵר דָּבָר בְּשֵׁם אוֹמְרוֹ, הָא לָמַדְתָּ שֶׁכָּל הָאוֹמֵר דָּבָר בְּשֵׁם אוֹמְרוֹ מֵבִיא גְאֻלָּה לָעוֹלָם, שֶׁנֶּאֱמַר (אסתר ב) וַתֹּאמֶר אֶסְתֵּר לַמֶּלֶךְ בְּשֵׁם מָרְדֳּכָי:
Greater is learning Torah than the priesthood and than royalty, for royalty is acquired by thirty stages, and the priesthood by twenty-four, but the Torah by forty-eight things. By study, Attentive listening, Proper speech, By an understanding heart, By an intelligent heart, By awe, By fear, By humility, By joy, By attending to the sages, By critical give and take with friends, By fine argumentation with disciples, By clear thinking, By study of Scripture, By study of Mishnah, By a minimum of sleep, By a minimum of chatter, By a minimum of pleasure, By a minimum of frivolity, By a minimum of preoccupation with worldly matters, By long-suffering, By generosity, By faith in the sages, By acceptance of suffering. [Learning of Torah is also acquired by one] Who recognizes his place, Who rejoices in his portion, Who makes a fence about his words, Who takes no credit for himself, Who is loved, Who loves God, Who loves [his fellow] creatures, Who loves righteous ways, Who loves reproof, Who loves uprightness, Who keeps himself far from honors, Who does not let his heart become swelled on account of his learning, Who does not delight in giving legal decisions, Who shares in the bearing of a burden with his colleague, Who judges with the scales weighted in his favor, Who leads him on to truth, Who leads him on to peace, Who composes himself at his study, Who asks and answers, Who listens [to others], and [himself] adds [to his knowledge], Who learns in order to teach, Who learns in order to practice, Who makes his teacher wiser, Who is exact in what he has learned, And who says a thing in the name of him who said it. Thus you have learned: everyone who says a thing in the name of him who said it, brings deliverance into the world, as it is said: “And Esther told the king in Mordecai’s name” (Esther 2:22).