"And their meal offerings and their libations" - even at night. But are libations offered at night? Was it not taught: I would know only of things whose manner is to be offered at night, and so forth, and at any rate it teaches that the meal offering of libations is by day? Rav Yosef said: Strike out "libations" from here. When Rav Dimi went up, he found Rabbi Yirmeya sitting and saying in the name of Rabbi Yehoshua ben Levi: From where do we learn that libations coming with a sacrifice are offered only by day? Scripture teaches, "for your libations and for your peace offerings" (Numbers 29:39) - it likens libations to peace offerings: just as peace offerings are by day, so libations are by day. He said: Who will provide me a man to write a letter? - send word to Rav Yosef that he should not strike "the meal offering of libations" from that teaching, for there is no difficulty: here the case is libations coming with a sacrifice, there it is libations coming on their own. And if he could find a man to write a letter - but did not Rabbi Abba, son of Rabbi Chiyya bar Abba, say in the name of Rabbi Yochanan: Those who write down the [oral] traditions are like those who burn the Torah, and one who learns from them receives no reward? For Rabbi Yehuda bar Nachmani, the interpreter of Rabbi Shimon ben Lakish, expounded: One verse says, "Write for yourself these words" (Exodus 34:27), and one verse says, "for according to the mouth of these words" - to tell you that words given orally you are not permitted to recite in writing, and those given in writing you are not permitted to recite by heart. They said: A new matter is different, for Rabbi Yochanan and Resh Lakish would study books of aggadah on the Sabbath and would expound thus: "It is a time to act for the LORD; they have voided your Torah" (Psalms 119:126) - better that one letter of the Torah be uprooted than that the Torah be forgotten from Israel. Rav Pappa said: Now that you have said that libations coming on their own are offered even at night, if libations came his way at night, he sanctifies them at night and offers them at night. Rav Yosef, son of Rav Shemaya, said to him: A teaching supports you: This is the rule - whatever is offered by day is sanctified only by day, and whatever is offered at night is sanctified whether by day or by night. Rav Adda bar Ahava said: The break of dawn disqualifies them, as it does the limbs.
Libations by Night and the Warning Against Writing the Oral Torah
Yalkut Shimoni on Torah 481:1
וּמִנְחָתָם וְנִסְכֵּיהֶם אֲפִלּוּ בַּלַיְלָה. (וּמִנְחָתָם) [וּנְסָכִים] מִי קָרְבֵי בַּלַּיְלָה וְהָתַנְיָא אֵין לִי אֶלָּא דְּבָרִים שֶׁדַּרְכּוֹ לִקְרַב בַּלַּיְלָה, וְכוּ' קְתָנֵי מִיהַת מִנְחַת נְסָכִים בַּיּוֹם. אָמַר רַב יוֹסֵף סַמִי מִכָּאן נְסָכִים. כִּי סַלִיק רַב דִּימִי אַשְׁכְּחֵיהּ לְרַבִּי יִרְמִיָּה דְּיָתִיב וַאֲמַר מִשְּׁמֵיהּ דְּרַבִּי יְהוֹשֻׁעַ בֶּן לֵוִי מִנַּיִן לִנְסָכִים הַבָּאִים עִם הַזֶּבַח שֶׁאֵין קְרֵבִין אֶלָּא בַּיּוֹם, תַּלְמוּד לוֹמַר (שם כט, לט) "לְנִסְכֵּיכֶם וּלְשַׁלְמֵיכֶם" מַקִּישׁ נְסָכִים לִשְׁלָמִים מַה שְּׁלָמִים בַּיּוֹם אַף נְסָכִים בַּיּוֹם. אֲמַר מָאן יָהִיב גַּבְרָא וּכְתִיב אִגַּרְתָּא, שְׁלַח לֵיהּ לְרַב יוֹסֵף דְּלָא תִּסְמֵי מִנְחַת נְסָכִים מֵהַךְ מַתְנִיתִין, דְּלֹא קָשְׁיָא, כָּאן בִּנְסָכִים הַבָּאִים עִם הַזֶּבַח, כָּאן בִּנְסָכִים הַבָּאִים בִּפְנֵי עַצְמָן, וְאִי מַשְׁכַּח גַּבְרָא כְּתַב אִגַּרְתָּא, וְהַאָמַר רַבִּי אַבָּא בְּרֵיהּ דְּרַבִּי חִיָּא בַּר אַבָּא אָמַר רַבִּי יוֹחָנָן כּוֹתְבֵי סְפָרִים כְּשׂוֹרְפֵי תּוֹרָה וְהַלּוֹמֵד מֵהֶם אֵין לוֹ קִבּוּל שָׂכָר, דִּדְרַשׁ רַבִּי יְהוּדָה בַּר נַחְמָן מְתוּרְגְּמָנֵיהּ דְּרַבִּי שִׁמְעוֹן בֶּן לָקִישׁ כָּתוּב אֶחָד אוֹמֵר (שמות לד, כז) "כְּתֹב לְךָ אֶת הַדְּבָרִים הָאֵלֶּה" וְכָתוּב אֶחָד אוֹמֵר "כִּי עַל פִּי הַדְּבָרִים הָאֵלָּה", לוֹמַר לְךָ דְּבָרִים שֶׁבְּעַל פֶּה אִי אַתָּה רַשַּׁאי לְאָמְרָם בִּכְתָב, וְשֶׁבִּכְתָב אִי אַתָּה רַשַּׁאי לְאָמְרָם עַל פֶּה. אָמְרֵי, מִלְּתָא חָדְתָא שָׁאֲנִי, דְּהָא רַבִּי יוֹחָנָן וְרֵישׁ לָקִישׁ מְעַיְינֵי בְּאַגָּדָתָא בְּשַׁבָּתָא וְדָרְשֵׁי הָכִי (תהלים קיט, קכו) "עֵת לַעֲשׂוֹת לַה' הֵפֵרוּ תּוֹרָתֶךָ" מוּטָב תֵּעָקֵר אוֹת אַחַת מִן הַתּוֹרָה וְאַל תִּשְׁתַּכַּח תּוֹרָה מִיִּשְׂרָאֵל. אֲמַר רַב פַּפָּא הַשְׁתָּא דְּאָמַרְתְּ נְסָכִים הַבָּאִים בִּפְנֵי עַצְמָן קְרֵבִין אֲפִלּוּ בַּלַּיְלָה, נִזְדַּמְּנוּ לוֹ נְסָכִים בַּלַּיְלָה מְקַדְּשָׁן, בַּלַּיְלָה וּמַקְרִיבָן בַּלַּיְלָה. אֲמַר לֵיהּ רַב יוֹסֵף בְּרֵיהּ דְּרַב שְׁמַעְיָה תַּנְיָא דִּמְסַיֵּעַ לָךְ, זֶה הַכְּלָל כָּל הַקָּרֵב בַּיּוֹם אֵינוֹ קָדוֹשׁ אֶלָּא בַּיּוֹם וְהַקָּרֵב בַּלַּיְלָה קָדוֹשׁ בֵּין בַּיּוֹם בֵּין בַּלַּיְלָה. אָמַר רַב אַדָּא בַּר אַהֲבָה עַמּוּד הַשַּׁחַר פּוֹסֶלֶת בָּהֶן כְּאֵיבָרִים.