The Talmud reconstructs the day-by-day chronology of the Sinai revelation, identifying which events occurred on which days of Sivan, providing the calendrical foundation for distinguishing the 2nd of Sivan as a unique moment in the sequence.
תָּנוּ רַבָּנַן: בְּשִׁשִּׁי בַּחֹדֶשׁ נִיתְּנוּ עֲשֶׂרֶת הַדִּבְּרוֹת לְיִשְׂרָאֵל. רַבִּי יוֹסֵי אוֹמֵר: בְּשִׁבְעָה בּוֹ. אָמַר רָבָא: דְּכוּלֵּי עָלְמָא בְּרֹאשׁ חֹדֶשׁ אֲתוֹ לְמִדְבָּר סִינַי. כְּתִיב הָכָא: ״בַּיּוֹם הַזֶּה בָּאוּ מִדְבַּר סִינָי״, וּכְתִיב הָתָם: ״הַחֹדֶשׁ הַזֶּה לָכֶם רֹאשׁ חֳדָשִׁים״ — מָה לְהַלָּן רֹאשׁ חֹדֶשׁ, אַף כָּאן רֹאשׁ חֹדֶשׁ. וּדְכוּלֵּי עָלְמָא, בְּשַׁבָּת נִיתְּנָה תּוֹרָה לְיִשְׂרָאֵל. כְּתִיב הָכָא: ״זָכוֹר אֶת יוֹם הַשַּׁבָּת לְקַדְּשׁוֹ״, וּכְתִיב הָתָם: ״וַיֹּאמֶר מֹשֶׁה אֶל הָעָם זָכוֹר אֶת הַיּוֹם הַזֶּה״ — מָה לְהַלָּן בְּעִצּוּמוֹ שֶׁל יוֹם, אַף כָּאן בְּעִצּוּמוֹ שֶׁל יוֹם. כִּי פְּלִיגִי בִּקְבִיעָא דְיַרְחָא: רַבִּי יוֹסֵי סָבַר — בְּחַד בְּשַׁבָּא אִיקְּבַע יַרְחָא, וּבְחַד בְּשַׁבָּא לָא אֲמַר לְהוּ וְלָא מִידֵּי מִשּׁוּם חוּלְשָׁא דְּאוֹרְחָא; בִּתְרֵי בְּשַׁבָּא אֲמַר לְהוּ: ״וְאַתֶּם תִּהְיוּ לִי מַמְלֶכֶת כֹּהֲנִים״;
The Sages taught: On the sixth day of the month of Sivan, the Ten Commandments were given to the Jewish people. Rabbi Yosei says: On the seventh day of the month. Rava said: Everyone agrees that the Jews came to the Sinai desert on the New Moon, as it is written here: “In the third month after the children of Israel were gone forth out of the land of Egypt, the same day came they into the wilderness of Sinai” (Exodus 19:1), without elaborating what day it was. And it is written there: “This month shall be to you the beginning of months; it shall be the first month of the year to you” (Exodus 12:2). Just as there, the term “this” is referring to the New Moon, so too, here the term is referring to the New Moon. And similarly, everyone agrees that the Torah was given to the Jewish people on Shabbat, as it is written here in the Ten Commandments: “Remember the Shabbat day to keep it holy” (Exodus 20:8), and it is written there: “And Moses said to the people: Remember this day, in which you came out from Egypt, out of the house of bondage, for by strength of hand the Lord brought you out from this place; there shall be no leaven eaten” (Exodus 13:3). Just as there, the mitzva of remembrance was commanded on the very day of the Exodus, so too, here the mitzva of remembrance was commanded on the very day of Shabbat. Where Rabbi Yosei and the Sages disagree is with regard to the determination of the month, meaning which day of the week was established as the New Moon. Rabbi Yosei held: The New Moon was established on the first day of the week, and on the first day of the week He did not say anything to them due to the weariness caused by the journey. On the second day of the week, He said to them: “And you shall be to Me a kingdom of priests and a holy nation; these are the words that you shall speak to the children of Israel” (Exodus 19:6).